GeolCarp_Vol64_No3_171

www.geologicacarpathica.sk

GEOLOGICA CARPATHICA

, JUNE 2013, 64, 3, 171—180 doi: 10.2478/geoca-2013-0018

Introduction

Gallium and germanium are relatively scarce elements and have
chemical characteristics similar to those of the common ele-
ments Al and Si, respectively. Minerals with substantial
amounts of Ga and Ge are rare. Gallium forms only several rare
species such as gallite (CuGaS

) and sohngeite (Ga(OH)

). Ger-

manium forms about 25 rare species, such as germanite
(Cu

), renierite ((Cu,Zn)

(Ge,As)

), argy-

rodite (Ag

GeS

), and argutite (GeO

). Generally, Ga and Ge

are disseminated in rocks in minerals of Al and Si (camou-
flage principle for trace element distribution according to
Goldschmidt 1937), which makes these two elements suit-
able geochemical tracers of past geological processes.

The known whole-rock and mineral abundances of Ga and

Ge  up  to1970  were  summarized  by  Wedepohl  (1972),  and
data  for  Ge  through  2006  were  published  by  Höll  et  al.
(2007). The reason for the little interest of petrologists in Ga
and Ge lies in the difficulty involved in chemically identifying
both  elements  because  their  contents  cannot  be  established
using conventional analytical methods such as X-ray fluores-
cence (XRF), atomic absorption spectrometry (AAS) or induc-
tively  coupled  plasma  with  optical  emission  spectrometry.
Nevertheless, Ga has recently been determined (using namely
the ICP-MS technique) in bulk-rock samples more frequently
than  Ge  (e.g.  Goodman  1972;  Argollo  &  Schilling  1978;
Collins  et  al.  1982;  Whalen  et  al.  1987;  Paktunc  &  Cabri
1995; Macdonald et al. 2007, 2010; Flude et al. 2008; Kelly et
al.  2008).  Selected  published  whole-rock  data  of  Ga  and  Ge
are summarized in Table 1.

Gallium and germanium geochemistry during magmatic

fractionation and post-magmatic alteration in different types

of granitoids: a case study from the Bohemian Massif

(Czech Republic)

KAREL BREITER

, NINA GARDENOVÁ

, VIKTOR KANICKÝ

and TOMÁŠ VACULOVIČ

Institute of Geology, Academy of Sciences of the Czech Republic, v.v.i., Rozvojová 269, CZ-165 00 Praha 6-Lysolaje, Czech Republic;

breiter@gli.cas.cz

Faculty of Science, Masaryk University, Kotlářská 2, CZ-611 37 Brno, Czech Republic

CEITEC, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic

(Manuscript received October 19, 2012; accepted in revised form March 14, 2013)

Abstract: Contents of Ga and Ge in granites, rhyolites, orthogneisses and greisens of different geochemical types from
the Bohemian Massif were studied using inductively coupled plasma mass spectrometry analysis of typical whole-rock
samples. The contents of both elements generally increase during fractionation of granitic melts: Ga from 16 to 77 ppm
and Ge from 1 to 5 ppm. The differences in Ge and Ga contents between strongly peraluminous (S-type) and slightly
peraluminous (A-type) granites were negligible. The elemental ratios of Si/1000Ge and Al/1000Ga significantly de-
creased during magmatic fraction: from ca. 320 to 62 and from 4.6 to 1.2, respectively. During greisenization, Ge is
enriched and hosted in newly formed hydrothermal topaz, while Ga is dispersed into fluid. The graph Al/Ga vs. Y/Ho
seems to be useful tool for geochemical interpretation of highly evolved granitoids.

Key words: ICP-MS, geochemistry, granites, gallium, germanium.

The relative behaviour of pairs of chemical elements with

similar  geochemical  properties  has  been  studied  for  many
years. Pairs of chemical elements with identical valence bonds
but different deeper electron structures behave in similar man-
ners both chemically and geochemically (Goldschmidt 1937;
Clarke 1992; Best 2003; Shaw 2006). They have similar ionic
radii  and  ionization  potentials.  Particularly  important  is  the
fact,  that  proportions  of  such  pairs  of  chemical  elements  are
independent of their absolute abundances. Different properties
of  the  deeper  atomic  structure,  which  may  induce  change  in
element  proportions,  are  manifested  only  in  specific  condi-

Material

Source

Earth

Webelement*

1.4

Chondrite

Anders & Grevesse (1989) 10

Oceanic bazalt

Paktunc & Cabri (1995)

14–25

Granites

Collins et al. (1982)

12–22

I-type granites

Whalen et al. (1987)

16±2

S-type granites

Whalen et al. (1987)

17±2

A-type granites

Whalen et al. (1987)

24.6±6

Rhyolite, granite

Shaw (1957)

Tonalite, granodiorite Shaw (1957)

21.4

Alkaline rhyolite

Macdonald et al. (2010)

29–33

Hawaiian bazalt

Argollo & Schilling (1978) 18–27 1.1–1.5

Granites

Wedepohl et al. (1972)

15–35

1–3

Alkaline rocks

Wedepohl et al. (1972)

20–76

1–3

Rhyolitic glases

Macdonald et al. (2007)

2.2–3.9

Granites Bernstein

(1985)

0.5–4.0

Table 1: Published contents of Ga and Ge in magmatic rocks (ppm).

* – www.webelements.com

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GEOLOGICA CARPATHICA, 2013, 64, 3, 171—180; Electronic Supplement, i

tions. This means that an unusual elemental ratio in a particu-
lar rock sample can provide information about specific pro-
cesses that occurred during the evolution of the rock.

Pairs of chemical elements, such as K-Rb, Nb-Ta or Zr-Hf,

have been studied because they play an essential role in pe-
trology  and  mineralogy  (Černý  et  al.  1986;  Clarke  1992;
Linnen  &  Kepler  1997;  Uher  et  al.  1998;  Finch  &  Hanchar
2003;  Hoskin  &  Schaltegger  2003;  Breiter  et  al.  2006,
2007b).  They  reflect  the  evolution  of  silicate  melts  through
fractional crystallization or fluid-melt immiscibility. In theo-
ry, Al-Ga and Si-Ge pairs may play a similar role in petro-
logical interpretations. However, in practice these pairs have
been  utilized  only  sporadically.  The  existing  petrological
studies of the behaviour of Ga and Ge during fractionation of
silicate  melts  have  focused  almost  exclusively  on  volcanic
rocks: Paktunc & Cabri (1995) compiled data for Ga in oce-
anic basalts ranging from 15 to 25 ppm. Argollo & Schilling
(1978)  studied  Si/Ge  and  Al/Ga  ratios  in  Hawaiian  basalts.
Macdonald  et  al.  (2007,  2010)  found  2.3—3.9 ppm  Ge  and
28.9—33.3 ppm  Ga  in  glassy  matrix  from  peralkaline  rhyo-
lites from the Kenya Rift Valley. The Al/Ga and Si/Ge ratios
in  aforementioned  rocks  range  between  1,000—10,000  and
100,000—1,000,000, respectively.

In the field of granitoids, Collins et al. (1982) and Whalen

et al. (1987) analysed 163 samples of different granitoids
containing 15—50 ppm Ga and proposed to use the Ga/Al ra-
tio for geochemical discrimination of A-type granites
(10000Ga/Al > 2.6, i.e. Al/Ga < 3800 in A-type granites). Ac-
cording to Cotton & Wilkinson (1980), GaF

complexes are

more stable in water-undersaturated melts than AlF

; this may

be the reason for the increase in Ga/Al ratios in A-type melts.

In the case of Ge, no models of its behaviour in magmatic

processes have been proposed. Wedepohl (1972) summa-
rized the Ge contents of granitoids from 1 to 3 ppm. Some
older studies stressed the enrichment of Ge during the greise-
nization of granites (Shcherba et al. 1966).

The aims of this paper, based on samples from the Bohe-

mian Massif, are: (1) to provide pilot data on contents of Ga
and  Ge  in  granitoids  of  different  geochemical  types;  (2)  to
discuss  the  changes  in  Al/Ga  and  Si/Ge  ratios  as  a  result  of
(i)  different  magma  protoliths  and  (ii)  different  degrees  of
fractionation; (3) to assess the possibility of using Al/Ga and
Si/Ge ratios for petrological considerations and interpretations.

Geological setting and studied samples

Within the Bohemian Massif, several contrasting types of

Paleozoic  granitoid  plutons  (Cháb  et  al.  2010)  occur.  The
complexes  of  granitic  rocks  (plutons)  selected  for  this  study
include the major types of magmas intruding during the Late
Cambrian and Carboniferous in Central Europe. Some of the
plutons  comprise  suites  of  intrusions  that  differ  in  their  de-
grees of fractionation, for example, in their contents of major
and trace elements. Therefore, the samples studied here com-
bine the differences resulting from the parent magma compo-
sition, with differences caused by melt fractionation and other
possible mechanisms. The following main types of Paleozoic
granitoid  plutons  in  the  Bohemian  Massif  were  collected
(Fig. 1, Table 2):

The Cambro-Ordovician peraluminous intrusive complex in

the Moldanubicum, which has been transformed into ortho-

Fig. 1. Distribution of the studied granitic plutons within the Bohemian Massif, Czech Republic (from Cháb et al. 2010, modified).
Black – orthogneiss, dark grey – granitoids, light grey – Variscan basement, white – post-Variscan sedimentary cover.

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Table 2: List of samples with contents of Si, Al, Ge and Ga including standard deviations (samples are ordered according to their approxi-
mate grade of differentiation within individual plutons or massifs). Continued on the next page.

No. Locality

Description

SiO

Ge Ga

Moldanubicum
orthogneisses, S-type

wt. % (SD) wt. % (SD) ppm (SD) ppm (SD)

4080

Zeliv, outcrop

Biotite orthogneiss

70.1 (0.4)

15.8 (0.3)

1.3 (0.1) 22.6 (0.4)

4069

Cetoraz, outcrop

Biotite orthogneiss

70.8 (0.4)

15.0 (0.2)

1.7 (0.1) 18.3 (0.7)

4066

Psárov, outcrop

Biotite orthogneiss

70.5 (0.5)

14.8 (0.2)

1.7 (0.2) 19.8 (0.9)

4072

Šelenberk near Mladá Vozice, outcrop

Biotite-muscovite orthogneiss

72.9 (0.3)

13.5 (0.1)

1.6 (0.1) 19.8 (0.4)

4074

Velký Blaník hill, outcrop

Biotite-muscovite orthogneiss

72.9 (0.6)

14.6 (0.3)

3.2 (0.3)

21 (1)

3266 Březí near Čáslav, outcrop

Biotite-muscovite orthogneiss

74.0 (0.5)

14.5 (0.2)

2.7 (0.3) 20.9 (0.5)

3796

Keblov, outcrop

Muscovite-tourmaline-biotite orthogneiss

72.8 (0.8)

14.6 (0.3)

2.7 (0.2) 19.1 (0.8)

3262 Quarry

Přibyslavice near Čáslav

Muscovite-tourmaline-garnet orthogneiss

75 (1)

14.6 (0.6)

4.3 (0.3) 27.9 (0.9)

Tis Pluton, S-type

3315

Lubenec outcrop

Biotite granodiorite

65.7 (0.6)

14.7 (0.2) 1.48 (0.06) 19.1 (0.4)

4658

Lubenec outcrop

Biotite granodiorite

72.9 (0.8)

13.3 (0.2)

1.5 (0.1)

20 (1)

3230

Outcrop Bába near Zihle

Biotite granite

73.9 (0.8)

13.3 (0.2)

1.3 (0.2)

18 (1)

3231

Quarry Tis

Biotite granite

73.7 (0.4)

13.1 (0.1) 1.44 (0.08) 18.3 (0.3)

4653

Quarry Stebno

Biotite granite

67.5 (0.7) 14.87 (0.3) 1.9 (0.2) 20.8 (0.6)

Central Bohemian
Pluton, I-type

4848 Quarry

Něčín

Biotite-hornblende granodiorite

74 (1)

13.8 (0.3) 1.50 (0.09) 14.3 (0.6)

4849

Quarry Krhanice

Biotite trondhjemite

63.6 (0.7)

18.8 (0.3)

1.6 (0.1) 16.8 (0.3)

4845

Quarry Kozárovice

Biotite-hornblende granodiorite

65.5 (0.8)

15.2 (0.2)

1.7 (0.1) 19.8 (0.3)

4846 Quarry

Hudčice

Biotite-hornblende granodiorite

63.0 (0.9)

15.5 (0.3)

1.8 (0.1) 21.6 (0.9)

4847

Quarry Vápenice

Biotite granodiorite

66 (1)

14.3 (0.4)

2.1 (0.2) 21.1 (0.5)

4850

Quarry Zernovka

Biotite granite

69 (1)

15.8 (0.2)

2.1 (0.2) 24.7 (0.4)

South Bohemian
Pluton, S-type

4084

Melechov massif, Šafranice hill, outcrop

Biotite (± muscovite) granite of Lipnice type

71.3 (0.8)

15.2 (0.3)

1.8 (0.1) 24.8 (0.4)

4231

Melechov massif, quarry Lipnice

Biotite (± muscovite) granite of Lipnice type

70.0 (0.5)

14.8 (0.2)

1.7 (0.2) 24.5 (0.6)

2793

Melechov massif, quarry Březinka

Two-mica granite of Kouty type

72.0 (0.7)

14.7 (0.1)

1.5 (0.2)

22 (1)

4265

Melechov massif, Svatojánské hutě, outcrop Two-mica granite of Kouty type

71 (1)

15.3 (0.3)

1.0 (0.1) 21.2 (0.7)

4089

Melechov massif, outcrops near Rohole

Two-mica granite of Eisgarn type

72.0 (0.4)

15.6 (0.2)

2.2 (0.2) 20.4 (0.4)

4093

Melechov massif, outcrops near Rohole

Two-mica granite of Eisgarn type

71.5 (0.6)

15.9 (0.2)

2.2 (0.1) 21.7 (0.7)

2772

Central massif, Kozí hora quarry

Fine-grained biotite granite with molybdenite 72.7 (0.6)

14.9 (0.2)

1.3 (0.1) 22.4 (0.4)

2761

Central massif, Lodhéřov, outcrop

Two-mica granite of Lásenice type

73.9 (0.8)

14.3 (0.3)

1.8 (0.1) 16.6 (0.6)

2771

Central massif, Kardašova Řečice quarry

Two-mica granite of Lásenice type

75.1 (0.6)

13.8 (0.3)

1.6 (0.1) 18.7 (0.5)

2782

Central massif, Mysletice quarry

Two-mica granite of Mrákotín type

72 (1)

14.8 (0.2)

1.6 (0.1) 22.1 (0.5)

3024

Central massif, quarry Mrákotín

Two-mica granite of Mrákotín type

73.3 (0.4)

14.1 (0.1)

1.3 (0.3) 24.1 (0.9)

2774

Central massif, Stálkov outcrop

Porfyritic two-mica granite Číměř type

74.3 (0.7)

13.7 (0.2)

1.7 (0.4) 23.9 (0.8)

2944

Central massif, Roznov outcrop

Porfyritic two-mica granite Číměř type

70.7 (0.7)

14.9 (0.2)

1.5 (0.1) 26.3 (0.4)

2962

Central massif, Langeg quarry

Porfyritic two-mica granite Číměř type

73.9 (0.8)

14.3 (0.3)

1.6 (0.1) 25.9 (0.5)

3009 Central

massif,

íměř quarry

Porfyritic two-mica granite Číměř type

73 (1)

14.3 (0.1)

1.8 (0.2) 23.7 (0.6)

2777 Central

massif,

Zvůle outcrop

Two-mica granite of Zvůle type

72.9 (0.8)

14.4 (0.2)

1.7 (0.1) 22.4 (0.7)

2940

Central massif, Valtinov outcrop

Two-mica granite of Eisgarn type

72 (1)

14.3 (0.4)

1.8 (0.1) 22.8 (0.8)

2949

Central massif, Griesbach outcrop

Two-mica granite of Eisgarn type

71.3 (0.6)

15.0 (0.2)

1.8 (0.2) 25.3 (0.6)

2954

Central massif, Grasselstein outcrop

Two-mica granite of Eisgarn type

74 (1)

14.1 (0.2)

2.3 (0.2) 27.3 (0.5)

2964

Central massif, Dreichsbach valley, outcrop Two-mica granite of Eisgarn type

71.3 (0.7)

14.6 (0.2)

2.8 (0.2) 26.8 (0.6)

2511

Central massif, Homolka hill, outcrop

Albite-Muscovite-Topaz granite

73.6 (0.6)

14.8 (0.2)

4.2 (0.2) 29.1 (0.5)

2512

Central massif, Homolka hill, outcrop

Albite-Muscovite-Topaz granite

72.8 (0.4)

15.1 (0.2)

5.4 (0.1) 26.4 (0.4)

2513

Central massif, Homolka hill, outcrop

Albite-Muscovite-Topaz granite

74.3 (0.8)

14.5 (0.6)

6.2 (0.2) 31.0 (0.6)

2476.

Central massif, debris Šejby

Pegmatoidal muscovite-garnet granite

73 (1)

14.3 (0.3)

5.5 (0.2) 33.1 (0.9)

2613

Central massif, debris Šejby

Pegmatoidal muscovite-garnet granite

73.4 (0.5)

15.5 (0.5)

4.5 (0.2) 35.1 (1)

4139

Plechý massif, outcrop Teufelschussel

Th-rich biotite (± muscovite) granite

71 (1)

14.2 (0.3)

1.7 (0.1) 29.4 (0.6)

4362

Plechý massif, outcrop Hebergrasberg hill

Th-rich biotite (± muscovite) granite

71.8 (0.2)

14.5 (0.2) 1.42 (0.03) 27.6 (0.1)

4368

Plechý massif, outcrop Trojmezná hill

Two-mica granite of Eisgarn type

73.6 (0.7)

14.4 (0.2)

1.6 (0.1) 21.3 (0.4)

3612

Plechý massif, debris near Pěkná

Two-mica granite of Eisgarn type

73.2 (0.2)

14.9 (0.1)

1.9 (0.1) 24.3 (0.6)

4363

Plechý massif, outcrop Dreisessel hill

Two-mica granite of Eisgarn type

73.2 (0.6)

14.0 (0.2)

1.7 (0.2) 33.0 (0.8)

4365

Plechý massif, outcrop Kamenná hill

Two-mica granite of Eisgarn type

72.4 (0.4)

14.3 (0.5)

1.6 (0.1) 23.7 (0.2)

Nejdek Pluton,
S-type granites

2924

Quarry Horní Rozmyšl

Biotite granite

72.4 (0.6)

13.9 (0.2)

2.2 (0.2) 20.1 (0.4)

2925

Quarry Mezihorská

Biotite granite

71.1 (0.6)

14.4 (0.2)

2.0 (0.3) 21.7 (0.8)

4742 Outcrop

Dračí skála

Biotite granite

71.5 (0.4)

14.2 (0.4)

1.5 (0.2) 22.5 (0.7)

4743

Outcrop Tisovský vrch hill

Biotite granite

72 (1)

14.7 (0.7)

1.3 (0.1) 22.4 (0.5)

4744

Outcrop Bílá skála

Biotite granite

74.8 (0.9)

13.3 (0.6)

1.2 (0.1) 27.0 (0.6)

4745 Quarry

the

erná valley

Li-enriched biotite granite with topaz

72.5 (0.8)

15.0 (0.3) 2.8 ( 0.3) 35.0 (0.8)

Podlesí stock,
S-type granites

3475

Podlesí, borehole PTP-3, depth of 199 m

Albite-Biotite granite

73.6 (0.9)

14.3 (0.3)

3.6 (0.5) 37.2 (0.6)

3490

Podlesí, borehole PTP-3, depth of 232 m

Albite-Biotite granite

73.8 (0.9)

14.6 (0.2)

5.0 (0.2) 37.5 (0.5)

3385

Podlesí, outcrop

Albite-Protolithionite-Topaz granite

73.8 (0.2)

14.6 (0.1)

3.4 (0.1) 32.5 (0.5)

3458

Podlesí, borehole PTP-3, depth of 82 m

Albite-Protolithionite-Topaz granite

73.2 (0.8)

14.8 (0.2)

3.6 (0.4)

36 (1)

3464

Podlesí, borehole PTP-3, depth of 106 m

Albite-Protolithionite-Topaz granite

73.7 (0.8)

14.4 (0.2)

3.6 (0.4)

34 (1)

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gneisses during the Variscan orogeny (intrusive age ca.
508 Ma; Vrána & Kröner 1995). This complex comprises
more than 20 bodies of biotite, two-mica and muscovite-gar-
net-tourmaline orthogneisses, the latter of which are enriched
in Na, P, B, and Sn (Breiter et al. 2005a).

The Tis Pluton (504 Ma; Venera et al. 2000) is a typical

representative of the Cambro-Ordovician peraluminous geo-
chemically primitive granites in the Teplá-Barrandian area in
Western Bohemia. The unmetamorphosed and only locally
slightly deformed Tis pluton is composed of biotite grano-
diorite and biotite granite (Breiter 2004).

The Central Bohemian Pluton (CBP) situated in the south-

central part of the Czech Republic is a typical composite plu-
ton  of  I-type  (350—336 Ma;  Holub  et  al.  1997a,b;  Janoušek
&  Skála  2011).  It  comprises  intrusive  suites  of  different
geochemical  types:  (i)  calc-alkaline  mostly  metaluminous
amphibole-biotite  tonalites  and  quartz  diorites  to  biotite
trondhjemites  and  granodiorites  with  associated  basic  rocks
(Sázava  suite);  (ii)  high-K  calc-alkaline  biotite ± amphibole
granodiorites  and  granites  (Blatná  suite);  (iii)  highly  K,
Mg-enriched  amphibole-biotite  melasyenites  and  melagran-
ites (durbachites) and associated K, Mg-rich biotite granites
(Čertovo  břemeno  suite);  and  (iv)  peraluminous  biotite
( ± muscovite)  granites  (Říčany  suite).  The  Sázava  suite  is
supposed to represent the melting of reworked material orig-
inating from a depleted mantle wedge and subducted oceanic
sediments, while rocks from the Blatná suite were generated
by the remelting of heterogeneous Neoproterozoic and Cam-
brian crust (Janoušek & Skála 2011). The high-K, Mg mela-
granitoids (durbachites) are believed to be the product of the

melting of the metasomatized upper mantle (Holub et al.
1997b).

The South Bohemian Pluton is a complex of Variscan per-

aluminous granites in southern Bohemia and northern Austria
(330—315 Ma). The pluton is composed of several composite
plutons;  the  largest  are  the  Melechov  Massif  on  the  north
(Breiter  &  Sulovský  2005),  the  Central  Massif  on  the  SE
(Breiter  &  Koller  1999)  and  the  Plechý  Massif  on  the  SW
(Breiter  et  al.  2007a).  Petrographically,  the  pluton  comprises
slightly deformed biotite > muscovite granites of Lipnice type,
slightly  deformed  two-mica  granites  of  Lásenice  type,  unde-
formed  two-mica  granites  (Mrákotín,  Číměř  and  Aalfang
types),  younger  fractionated  two-mica  granites  (Eisgarn  type
s.s. according to Waldmann 1950) and topaz-muscovite gran-
ites enriched in Na, P, F, Rb, Sn and Nb. All these rocks repre-
sent  the  product  of  voluminous  melting  of  crustal  rocks
(Breiter  &  Scharbert  1995;  Finger  et  al.  1997;  Gerdes  et  al.
1998). The Weinsberg and Mauthausen massifs (Finger et al.
1997) located further to the south in Austria are not included
in this study.

The Nejdek Pluton is the most typical example of a strongly

peraluminous rare metal-bearing pluton in the western Krušné
Hory/Erzgebirge area. This pluton is composed of two suites
traditionally  described  as  “intrusive  complexes”.  The  older
intrusive  complex  is  composed  of  several  textural  types  of
biotite  granites,  while  the  younger  intrusive  complex  com-
prises biotite granites followed by intrusions of F, P, Li, Rb,
Sn, and U-enriched Li-mica-topaz granites (ca. 330—312 Ma;
Breiter et al. 1999; Förster et al. 1999). This evolution termi-
nated in the extremely fractionated P-, F-, Na-, Li-, Sn-, Nb-,

Table 2: Continued from the previous page.

No. Locality

Description

SiO

Ge Ga

Podlesí stock,
S-type granites

wt. % (SD) wt. % (SD) ppm (SD) ppm (SD)

3511

Podlesí, borehole PTP-3, depth of 348 m

Albite-Protolithionite-Topaz granite

72.6 (0.7)

14.8 (0.2)

4.1 (0.2) 34.4 (0.5)

3413

Podlesí, quarry

Albite-Zinnwaldite-Topaz granite

73 (2)

16 (1)

3.9 (0.2) 52.6 (0.8)

3414

Podlesí, quarry

Albite-Zinnwaldite-Topaz granite

70.7 (0.9)

15.9 (0.8)

4.4 (0.3) 54.5 (0.5)

3416

Podlesí, quarry

Albite-Zinnwaldite-Topaz granite

70 (1)

15.8 (0.5)

3.9 (0.3)

69 (1)

3417

Podlesí, quarry

Albite-Zinnwaldite-Topaz granite

66.5 (0.7)

17.8 (0.4)

4.4 (0.4)

77 (1)

3366

Podlesí, outcrop

Biotite-Topaz greisen

77.6 (0.6)

14.9 (0.2)

8.8 (0.4) 10.9 (0.5)

3387

Podlesí, outcrop

Zinwaldite-Topaz greisen

82 (2)

13.2 (0.9)

7.6 (0.6) 7.8 (0.6)

Hora Svaté Kateřiny,
A-type granites

4471 Hora

Svaté

Kateřiny stock, debris

Albite-Biotite granite

76.6 (0.8)

12.2 (0.2)

2.5 (0.2) 31.7 (0.9)

4604 Hora

Svaté

Kateřiny stock, debris

Albite-Biotite granite

77.1 (0.6)

12.6 (0.2)

3.1 (0.3) 40.1 (0.1)

3097 Hora

Svaté

Kateřiny stock, debris

Albite-Zinnwaldite granite

74.2 (0.5)

13.2 (0.3)

3.7 (0.1) 38.3 (0.9)

4554 Hora

Svaté

Kateřiny stock, debris

Albite-Zinnwaldite granite

75.5 (0.7)

12.6 (0.3)

3.4 (0.3) 37.7 (0.7)

Teplice caldera,
A-type rocks

3194

Mikulov, borehole Mi-4, depth of 50 m

Rhyolite ignimbrite

76 (1)

12.3 (0.6)

1.6 (0.3)

21 (1)

3198

Mikulov, borehole Mi-4, depth of 178 m

Rhyolite ignimbrite

74.7 (0.4)

12.3 (0.2)

1.4 (0.3)

20 (1)

3201

Mikulov, borehole Mi-4, depth of 285 m

Rhyolite ignimbrite

76.4 (0.5)

12.3 (0.2) 1.13 (0.06) 18.1 (0.2)

3207

Mikulov, borehole Mi-4, depth of 483 m

Rhyolite ignimbrite

77.1 (0.8)

11.6 (0.2)

2.3 (0.2) 24.4 (0.8)

3208

Mikulov, borehole Mi-4, depth of 512 m

Rhyolite ignimbrite

76.4 (0.8)

11.8 (0.4)

1.4 (0.1) 20.3 (0.6)

3210

Mikulov, borehole Mi-4, depth of 579 m

Rhyolite ignimbrite

75.8 (0.7)

12.2 (0.1)

1.9 (0.1) 21.2 (0.4)

3211

Mikulov, borehole Mi-4, depth of 608 m

Rhyolite ignimbrite

61 (1)

24.4 (0.5)

2.3 (0.2)

32 (1)

3532 Loučná hill outcrop

Granite porphyry

68.9 (0.5)

14.7 (0.1)

1.9 (0.1) 23.9 (0.2)

3376

Frauenstein outcrop

Granite porphyry

68.1 (0.8)

14.7 (0.3)

1.7 (0.1) 23.7 (0.6)

4686

Cínovec, borehole CS-1, depth of 336 m

Albite-Zinnwaldite granite

76 (2)

13.6 (0.7)

2.9 (0.3)

47 (1)

4687

Cínovec, borehole CS-1, depth of 413 m

Albite-Zinnwaldite granite

76 (2)

12.5 (0.4)

3.0 (0.4)

40 (1)

4691

Cínovec, borehole CS-1, depth of 749 m

Biotite granite

76 (1)

12.8 (0.1)

2.8 (0.2)

35 (1)

4692

Cínovec, borehole CS-1, depth of 988 m

Biotite granite

75 (2)

12.5 (0.2)

1.5 (0.2) 28.9 (0.9)

4693

Cínovec, borehole CS-1, depth of 1579 m

Biotite granite

76 (2)

12.6 (0.4)

1.7 (0.1) 32.4 (0.7)

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Ta-, and W-enriched Podlesí stock with examples of layered
rocks, unidirectional solidification textures and greiseniza-
tion (Breiter et al. 2005b).

The Hora Svaté Kateřiny intrusion forms a small stock of

strongly fractionated subvolcanic A-type granites in the cen-
tral part of the Krušné hory/Erzgebirge (308 Ma; Breiter
2008).

The late-Variscan A-type volcano-plutonic complex of the

eastern Erzgebirge (Altenberg-Teplice caldera) comprises co-
magmatic slightly peraluminous “Teplice rhyolite” (309 Ma;
Hoffmann et al. 2013) and slightly younger rare metal granites
of the Cínovec Pluton (Breiter 2012).

Contents of Si, Al, K, Ga and Ge, as well as some trace el-

ements, were analysed in typical whole-rock samples repre-
senting the magmatic evolution of all of the aforementioned
plutons (Table 2).

Analytical methods

Contents of Al, Si, Ga and Ge were determined using

ICP-MS  in  the  laboratory  of  the  Department  of  Chemistry,
Masaryk University Brno, Czech Republic. Whole-rock grani-
toid  samples  and  the  certified  reference  material  (CRM
GBW07406,  National  Reasearch  Center  for  CRMs,  China)
were decomposed using fusion with LiBO

(Spectromelt A20,

Merck), (0.2 g of a sample with 1.0 g of LiBO

). The resulting

borosilicate glass bead was dissolved under stirring in 20 ml
of 0.7 mol/l HNO

, the solution was transferred into a volu-

metric  flask  and  after  addition  of  internal  reference  element
(Se)  filled  up  250 ml  with  deionized  water.  Blank  solutions
were  prepared  in  the  same  way  as  the  samples.  The  set  of  6
calibration solutions containing Ga and Ge in the range from 0
to 200 µg/l were used for their determination in samples. For
suppressing of matrix effect caused by HNO

all the calibra-

tion solutions were prepared using 0.06 mol/l HNO

and sele-

nium was used as an internal standard. The ICP spectrometer
(Agilent, 7500CE, Sta Clara, CA, USA) is equipped with col-
lision-reaction cell for suppressing possible isobaric interfer-
ences. The generator power input was 1500 W, outer plasma
gas flow rate (Ar) 15.0 l . min

—1

, intermediate plasma gas flow

rate (Ar) 0.25 l . min

—1

, carrier gas (Ar) flow-rate 0.85 l . min

—1

sample flow rate 200 µl . min

—1

, nebulizer temperature 2 °C

and He flow-rate in collision cell was 3 ml . min

—1

. The fol-

lowing isotopes were recorded for Al, Si, Ga and Ge determi-
nation:

Al,

Si,

Ga,

Ge and

Ge. Due to strong

isobaric interferences

Ar and

Fe, which was sup-

pressed insufficiently by collision reaction cell, the isotopes

Ga and

Ge were only used for determination. For quality

control the CRM GBW7406 was analysed in each set of dis-
solved samples.

The content of potassium was analysed in the laboratory of

the  Czech  Geological  Survey,  Prague  using  the  atomic  ab-
sorption  method.  Replicate  analyses  of  international  refer-
ence  material  (JG-3  granodiorite;  Geological  Survey  of
Japan) yield an average error (1  ) of  ± 1 % with respect to
recommended  values  (Govindaraju  1994).  The  trace  ele-
ments (Rb, Y, Ho) were determined by ICP mass spectrome-
try  following  a  lithium  metaborate/tetraborate  fusion  and

nitric acid digestion of a 0.2 g sample in the laboratory of
ACME, Vancouver, Canada. (Details in http://acmelab.com/.)

The accuracy of determination of Ga and Ge was checked

by analysis of CRM GBW7406. The results of Ga and Ge de-
termination  and  their  limits  of  detection  (LOD)  are  given  in
Table 3. The average content is calculated from 6 analyses of
the  CRM.  Accuracy  was  statistically  tested  and  no  significant
differences  between  certified  and  determined  values  were
found. LOD was calculated according to IUPAC 3  definition.

LOD

;

where 3

is standard deviation of blank calculated from

5 replicates, S is slope of calibration line of given isotope.

Ga Ge

Measured content [mg/kg]

32 ± 2

3.4 ± 0.3

Certified value [mg/kg]

30 ± 3

3.2 ± 0.3

Table 3: Results of determination of Ga and Ge in certified refer-
ence material GBW7406.

Results

The contents of Al, Si, Ga and Ge, including their standard

deviations, in the analysed granites, rhyolites and orthog-
neisses are summarized in Table 2 and illustrated in Fig. 2. It
follows from Table 2 that the contents of Ge and Ga are well
above their LODs. The complete data set used for figure con-
structions is accessible as an electronic attachment.

The Al-contents in A-type rocks is distinctly lower (6.6—

7.2 wt. % Al, 12.5—13.6 wt. % Al

) than in S- and I-type

rocks (7.0—8.4 wt. % Al, 13.3—15.9 wt. % Al

). The con-

tent of 6.8 wt. % Al (12.85 wt. % Al

) can serve as useful

value for discrimination of A-type granitoids.

The content of Si in A-type granites (mostly 34.7—

36.0 wt. % Si, 74.2—77.1 wt. % SiO

) is generally higher

than those in S-type granites (mostly 33.0—34.5 wt. % Si,
70.7—73.7 wt. % SiO

) and I-type rocks (29.4—34.6 wt. % Si,

63—74 wt. % SiO

). Only several samples have Si-contents

outside the aforementioned intervals: quartz-rich greisen of
S-type granites (up to 38.3 wt. % Si, 81.8 wt. % SiO

), some

S-type granodiorites (down to 30.6 wt. % Si, 65.7 wt. %
SiO

) and A-type granite porphyry (down to 31.8 wt. % Si,

68.1 wt. % SiO

). The content of 35 wt. % Si (ca. 75 wt. %

SiO

) can discriminate the majority of the A-type rocks.

The Ga contents in the studied samples range from 7.8 to

77.4 ppm. The values for the less- and moderately fractionated
rock types range from 14 to ca. 35 ppm. Higher values were
found in strongly fractionated rare-metal A-type granites (up
to 47 ppm) and strongly peraluminous S-type granites (up to
77 ppm).  The  lowest  contents  were  found  in  hydrothermal
greisens  of  peraluminous  granites  (less  than  10 ppm).  The
Al/1000Ga values varied between 1.2 and 5.9 in granites and
rhyolites,  between  2.8  and  4.4  in  orthogneisses,  and  between
7.2 and 9 in greisens.

The Ge contents vary from 1.0 to 8.8 ppm. Most of the

less and moderately fractionated granitoids exhibited ranges

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of 1.5 to 2.5 ppm, and the highly fractionated ones had ranges
of  2.5  to  5 ppm.  The  highest  values,  7.6  and  8.8 ppm,  were
found  in  metasomatic  greisens.  The  Si/1000Ge  ratio  varies
from 100 to 320 in less fractionated granites and rhyolites and
from 69 to 125 in highly fractionated granites. The Si/1000Ge
values in orthogneisses are similar to those of granites, rang-
ing  from  81.8  to  246.  The  lowest  Si/1000Ge  values  (41—50)
were found in greisens of peraluminous granites.

Discussion

In more places through the text we use the term “fraction-

ated granites”. This term refers to rocks to varying degrees
enriched with some LILE (large-ion lithophile elements like
K, Rb, Cs), HFSE (high field strength elements like U, Nb,
Ta, Sn, W) and fluxing agents (F, P, H

O) which generally

underwent long fractional crystallization from the primary
melt. These rocks are also called “specialized granites” or
“rare-metal granites”. From the mineralogical point of view,
they are usually composed of albite, K-feldspar, quartz, Li-
bearing mica and topaz (or fluorite). For this group of rocks
there is no universally applicable index of fractionation. In-
crease of silica, widely used for this purposes in Harker’s di-

agrams, is not applicable here. In the most evolved peralumi-
nous rocks, due to enrichment in alkalis, fluorine and phos-
phorus, silica decreases (Förster et al. 1999; Breiter et al.
2005b). Förster et al. (1999) proposed to use for this purpose
the value 1/TiO

. According to our opinion, the traditional

K/Rb-value is well applicable marker of fractionation for all
geochemical types of rock (I-, S- and A-types) and it is ap-
plied in this paper. We use the term “fractionated granites”
for rocks with K/Rb < 75.

Changes in Al/Ga and Si/Ge values during pluton evolution

The most widely used chemical indicator of evolution of

magmatic rocks is the K/Rb value (Clarke 1992). Rubidium
has  a  larger  ionic  radius  than  the  potassium,  making  it  less
compatible with the crystal lattice of common K-bearing sili-
cates.  As  a  consequence,  K  preferentially  concentrates  in
crystallizing  minerals  during  melt  crystallization,  while  Rb
remains in the residual melt. This results in a systematic de-
crease  in  K/Rb  value  during  fractional  evolution  of  the  pa-
rental melt.

Our study includes plutons composed of (i) suits with dif-

ferent protoliths (Central Bohemian Pluton), (ii) group of re-
peated intrusions from the same source (Nejdek Pluton,

Fig. 2. a – Graph of Al vs. Ga. The highest Ga contents were detected in extremely fractionated facies of S-type granites in the western
part of the Krušné Hory Mountains. The lowest contents of Ga were found in greisens. The contents of Al are slightly lower in A-type gran-
itoids. The Al/Ga values are depicted in the right part of the graph. b – Graph of Si vs. Ge. The Ge content increases only slightly during
the differentiation of plutons from 1—2 ppm to 4—5 ppm. The highest Ge contents were found in quartz-topaz greisens (7—9 ppm). The Si/Ge
values are depicted in the right of the graph. c – Graph Al/1000Ga vs. K/Rb illustrates changes in the Al/Ga-ratio during evolution of indi-
vidual plutons. d – Graph Si/1000Ge vs. K/Rb illustrates changes in the Si/Ge-ratio during evolution of individual plutons.

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Teplice caldera), and (iii) plutons combining both these prin-
ciples (South Bohemian Pluton, Rozvadov Pluton). In all
these cases, decrease of the K/Rb value clearly illustrates the
general geochemical evolution of the pluton: K/Rb decreases
from 300 in the early down to 20 in the final products of
magmatic evolution.

The differences in ionic radii and ionization potentials be-

tween Si and Ge and between Al and Ga indicate that a rela-
tive  Ge  and  Ga  enrichment  of  residual  melts  should  be
expected  (Goldschmidt  1937;  Wedepohl  1972).  As  result,
the  Si/Ge  and  Al/Ga  values  will  decrease  during  fraction-
ation.  Argollo  &  Schilling  (1978)  demonstrated  that  during
the crystallization of Hawaiian basalts, an increase of Ga and
Ge contents was simultaneously accompanied by an increase
of Al and Si contents; as a result, no systematic changes in
Si/Ge or Al/Ga values were observed in these basalts. In con-
trast, all studied granitic plutons from the Bohemian Massif
show distinct decrease in both ratios during fractionation, as
theoretically expected.

During magmatic evolution of individual plutons, the Al/Ga

values  generally  decreased  due  to  an  increase  in  Ga,  but  in-
creased during post-magmatic high-temperature hydrothermal
greisenization  due  to  a  strong  decrease  in  Ga  (Fig. 2c).  For
example, the Al/1000Ga-value decrease in the I-type Central
Bohemian Pluton from 5.1—5.9 in tonalites of the Sázava-suite
through 3.8—4.1 in granodiorites of the Blatná suite to 3.4 in
the  Říčany  granite.  In  the  S-type  granites  from  the  Nejdek
Pluton, this value decreased from 3.5—3.7 in the older biotite
granites  down  to  1.2  in  the  younger  albite-zinnwaldite  gran-
ites.  Similarly  in  the  A-type  caldera  system,  the  Al/1000Ga
value decreased from ca. 3.5 in rhyolites to  < 2 in zinnwaldite
granites. On the other side, in the S-type South Bohemian Plu-
ton this value scattered without any distinct trend.

Whalen et al. (1987) considered the Al/Ga ratio to be criti-

cal for distinguishing A- and S-type granitoids. According to
our  results,  this  criterion  cannot  be  applied  generally.  The
highest Ga contents were detected in strongly peraluminous
S-type granites: up to 67 ppm Ga (Al/1000Ga = 2.6) in a to-
paz-lepidolite  granite  at  Beauvoir,  France  (Raimbault  et  al.
1995)  and  77 ppm  Ga  (Al/1000Ga = 1.2)  in  albite-zin-
nwaldite  granite  at  Podlesí,  Czech  Republic  (this  paper).
This is more than in the A-type granites from the Erzgebirge
(32—47 ppm  Ga,  Al/1000Ga = 1.5—2.3;  this  paper)  or  in  the
highly fractionated A-type Madeira Complex in Brazil (max.
59 ppm  Ga,  Al/1000Ga = 2.2;  Lenharo  et  al.  2003).  Differ-
ences  in  the  ionic  potentials  of  Al  and  Ga  are  particularly
manifested in water- and F-rich residual melts where a distinct
relative  enrichment  with  Ga  occurs,  regardless  of  the  geo-
chemical type of parental magma. In contrast, the lowest con-
tents of Ga (7.8—10.9 ppm) and thus the highest Al/1000Ga
value (ca. 8) were found in greisens of peraluminous granites
where Ga was released during the hydrothermal decomposi-
tion of feldspars and partitioned into a fluid phase. While Al
was immediately incorporated into newly formed topaz, Ga
was washed out from the rock.

The Si/1000Ge ratio decreases during magmatic evolution

of some plutons, such as in the S-type Nejdek Pluton from
the western Erzgebirge (from ca. 295 in biotite granites to ca.
70 in albite-zinnwaldite granite), in the A-type caldera gran-

ites  from  the  eastern  Erzgebirge  (from  ca. 240  in  biotite
granite  to  ca. 120  in  zinnwaldite  granite)  and  in  the  I-type
Central Bohemian Pluton (from 229 in the Sázava tonalite to
156  in  the  Říčany  granite).  In  the  S-type  South  Bohemian
Pluton  the  Si/1000Ge  value  scattered  between  320  and  56
without correlation with the K/Rb value. But when we exam-
ine the samples from the South Bohemian Pluton in more de-
tail  (Fig. 3),  we  find  out  that  the  dispersion  of  data  has  a
geological background:

Samples from the Central Massif form one array, with posi-

tive correlation between Si/Ge- and K/Rb-values. We con-
clude that all these rock samples are products of fractionation
from one parental melt. The only sample positioned outside
this array is slightly altered and thus impoverished in Rb.

The samples from the Melechov Massif form three

groups  corresponding  to  different  textural  facies  within  the
massif:  the  fine-grained  two  mica  granite  of  Kouty  type
(Si/1000Ge = 320),  fine-grained  biotite > muscovite  granite

Fig. 3. Graph Si/1000Ge vs. K/Rb shows differences in geochemical
evolution of individual magmatic centers within the South Bohemian
Pluton.

Fig. 4. Graph of Al/Ga versus Si/Ge ratios for comparison of evolu-
tion of both values. The Si/Ge ratio more accurately illustrates the
general process of differentiation. Empirical field of highly frac-
tionated granites with limits Si/1000Ge < 150 and Al/1000Ga < 3 is
depicted. Greisens lie outside the magmatic trend. For symbol de-
scriptions, see Fig. 2.

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of Lipnice type (Si/1000Ge = 185—194) and coarse-grained
two-mica granite of Melechov type (148—155). In this case,
different enrichment in Ge, at the same K/Rb-value, may re-
sult from differences in protolith involved in melting of indi-
vidual intrusions.

In the case of the Plechý Massif, the scatter in both Si/Ge-

and K/Rb-values does not correspond to textural facies dis-
tinguished within the massif (Breiter et al. 2007a) and should
be interpreted as a result of the internal inhomogeneity of
this intrusive body.

When comparing the Si/Ge and Al/Ga ratios (Fig. 4), the

Si/Ge ratio more accurately illustrates the general process of
differentiation, which meant evolution from the primitive to
the more evolved melts. The same trend also follows during
high-temperature greisenization. The Al/Ga value can better
discriminate the latest highly fractionated rocks. However,
this value varies considerably in the crystallization products
of the late F-rich melts at Podlesí (enrichment in albite-rich
layered rocks) and products of hydrothermal alteration (de-
crease in greisens).

The Ge and Ga contents of Moldanubicum orthogneisses

correspond  to  their  overall  contents  in  granites  of  similar
composition,  which  indicates  that  neither  element  was  con-
siderably  redistributed  during  regional  amphibolite-facies
metamorphism.

Changes in water-rich melts and during hydrothermal
processes

The Y/Ho value changes little during fractional crystalli-

zation of silicate melts. However, this ratio appears to be
sensitive to processes occurring in residual water-rich melts
associated with the admixture of fluids (Bau 1996; Irber
1999).

A graph showing the Al/Ga vs. Y/Ho ratios (Fig. 5) illus-

trates the dissimilarity of various processes occurring during
the late stages of development of fractionated granites. The
majority of analysed S-type granite samples fall in a narrow
interval for both ratios that correspond to fractional crystalli-
zation of a common granite melt: the Al/1000Ga ratio ranges
from 4.5 to 1.5, and the Y/Ho ratio ranges from 30 to 40.

Fig. 5. Graph of Al/Ga versus Y/Ho ratios illustrates dissimilarity
of various processes occurring in the late evolution of granites. See
the text for explanation. For symbol descriptions, see Fig. 2.

Two samples with high Al/Ga values represent quartz-topaz
greisens  of  a  metasomatic  nature,  formed  when  Ga  was  re-
moved with the fluid phase during the alteration and decom-
position of primary feldspars and micas, while Al remained
fixed in authigenic micas and topaz. Four samples with low
Al/Ga  ratios  and  the  highest  Y/Ho  values  represent  the  ter-
minal  stage  of  fractional  crystallization  of  an  S-type  melt
rich in Na, F and water. In this case, the Ga content increased
(Al/1000Ga < 1.5), and the melt became completely depleted
of Ho, which entered zircon and, to a lesser extent, xenotime,
while  some  Y  remained  in  the  melt  (Y/Ho > 50).  A-type
granites  in  the  Bohemian  Massif  are  represented  only  with
strongly fractionated facies with low Al/Ga values. However,
even in this particular case, the Y/Ho values enable us to dis-
tinguish rocks that underwent only fractional crystallization
from  the  melt  (Y/Ho = 40—50),  from  rocks  with  miaroles,
which  argues  for  the  admixture  of  a  fluid  phase  from  the
melt (Y/Ho = 25—30). During this stage, xenotime, which was
the  primary  host  of  HREE,  was  destroyed,  and  secondary
REE minerals (fluorides, oxyfluorides and fluorocarbonates)
were  immediately  formed.  During  this  process,  Y  is  more
mobile than Ho (Breiter et al. 2009), which results in a de-
crease in the Y/Ho value in the rock (Y/Ho = 25—32).

Conclusions

The main results of this study of the distribution and be-

haviour of Ga and Ge in granites can be summarized as fol-
lows:

Gallium contents vary from 16 to 77 ppm in the studied

granitoids, and from 8 to 11 ppm in greisens.

Germanium contents range from 1 to 5 ppm in grani-

toids and from 8 to 9 ppm in greisens.

During fractionation, magma becomes relatively en-

riched with Ga and Ge, while the Si/Ge and Al/Ga values de-
crease.

Gallium contents and Al/Ga values can be used to distin-

guish A- and S-type granitoids only in a very limited way.

The maximum Ga enrichment occurs at the end of frac-

tionation of water- and F-rich melts, where the differences
between the ionic radii and complexation potentials of Ga
and Al become more distinct. The maximum contents of Ge
were detected in metasomatic greisens.

During hydrothermal greisenization, Ga becomes dis-

persed while Ge is conserved in newly crystallizing quartz
and topaz.

The metamorphism of amphibolite facies has no visible

effect on the distribution of Ge or Ga.

The Al/Ga vs. Y/Ho diagram seams to be useful tool for

discrimination of different kinds of highly evolved granitic
melt and products of their hydrothermal alteration.

Acknowledgments: This investigation was supported by the
Czech Science Foundation, Project No. P210/10/1309, RVO
67985831 and Project CEITEC (CZ.1.05/1.1.00/02.0068)
from the European Regional Development Fund. Compre-
hensive reviews by Igor Petrík and Jean-Clair Duchesne and
remarks by Igor Broska are acknowledged.

179

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GEOLOGICA CARPATHICA

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Electronic Edition of Supplement — BREITER et al.: Gallium and germanium geochemistry....

Contents of SiO

, Al

, and K

O (wt. %) and Ge, Ga, Rb, Y, and Ho (ppm) in analyzed samples

No.

SiO

Moldanubicum orthogneisses
4080

70.1

15.8

3.20

1.3

22.6

142

0.35

4069

70.8

15.0

4.41

1.7

18.3

217

0.80

4066

70.5

14.8

5.02

1.7

19.8

260

1.18

4072

72.9

13.5

5.24

1.6

19.8

391

1.24

4074

72.9

14.6

4.91

3.2

20.9

369

0.45

3266

74.0

14.5

4.38

2.7

20.9

329

0.30

3796

72.8

14.6

4.51

2.7

19.1

269

0.38

3262

74.7

14.6

3.89

4.3

27.9

573

4.0

0.11

Tis Pluton
3315

65.7

14.7

3.30

1.48

19.1

2.10

4658

72.9

13.3

2.88

1.5

1.86

3230

73.9

13.3

4.58

1.3

133

1.25

3231

73.7

13.1

4.54

1.44

18.3

149

0.74

4653

67.5

14.9

4.28

1.9

20.8

141

1.12

Central Bohemian Pluton
4848

74.0

13.8

2.48

1.5

14.3

0.33

4849

63.6

18.8

2.32

1.6

16.8

0.23

4845

65.5

15.2

3.81

1.7

19.8

182

0.58

4846

63.0

15.5

3.63

1.8

21.6

171

0.97

4847

66.0

14.4

5.47

2.1

21.1

318

0.79

4850

69.0

15.8

5.57

2.1

24.7

329

10.4

0.36

South Bohemian Pluton
4084

71.3

15.2

5.39

1.8

24.8

347

9.2

0.28

4231

70.0

14.8

5.36

1.7

24.5

321

0.49

2793

72.0

14.7

5.14

1.5

22.0

295

9.4

0.30

4265

71.4

15.3

5.35

1.0

21.2

328

10.6

0.35

4089

72.0

15.6

4.42

2.2

20.4

299

10.8

0.36

4093

71.5

15.9

4.58

2.2

21.7

308

11.3

0.40

2772

72.7

14.9

3.18

1.3

22.4

140

5.9

0.20

2761

73.9

14.3

4.60

1.8

16.6

252

7.9

0.26

2771

75.1

13.8

4.28

1.6

18.7

232

0.38

2782

72.1

14.8

5.33

1.6

22.1

289

7.8

0.22

3024

73.4

14.1

5.39

1.3

24.1

284

7.3

0.24

2774

74.3

13.7

4.27

1.7

23.9

291

10.0

0.33

2944

70.7

14.9

5.41

1.5

26.3

284

10.0

0.33

2962

73.9

14.3

4.60

1.6

25.9

252

7.9

0.26

3009

73.2

14.3

5.19

1.8

23.7

306

8.3

0.28

2777

72.9

14.4

4.66

1.7

22.4

290

9.9

0.33

2940

72.4

14.3

4.79

1.8

22.8

283

8.9

0.27

2949

71.3

15.0

5.91

1.8

25.3

382

7.4

0.23

2954

73.6

14.1

4.60

2.3

27.3

402

10.3

0.31

2964

71.3

14.6

5.12

2.8

26.8

335

10.4

0.31

2511

73.6

14.8

3.83

4.2

29.1

734

5.7

0.17

2512

72.8

15.1

3.23

5.4

26.4

1023

1.7

0.05

2513

73.4

15.5

3.14

4.0

29.8

1188

1.2

0.03

2476

73.4

14.3

2.39

5.5

33.1

574

1.6

0.05

2513

74.3

14.5

3.14

6.2

31.0

1188

1.2

0.03

4139

71.5

14.2

5.53

1.7

29.4

420

0.44

4362

71.8

14.5

5.21

1.4

27.6

405

0.54

4368

73.6

14.4

5.32

1.6

21.3

348

9.0

0.30

3612

73.2

14.9

4.85

1.9

24.3

374

0.31

4363

73.2

14.0

5.26

1.7

33.0

423

0.47

4365

72.4

14.3

4.99

1.6

23.7

457

0.43

Nejdek Pluton
2924

72.4

13.9

4.71

2.2

20.1

240

0.52

2925

72.4

14.4

4.80

2.0

21.7

260

0.54

4742

71.5

14.2

4.36

1.5

22.5

227

0.64

4743

72.1

14.7

4.58

1.3

22.4

250

0.51

4744

74.8

13.3

5.02

1.2

416

0.67

4745

72.5

15.0

4.62

2.8

978

0.39

Podlesí stock
3475

73.6

14.3

4.50

3.6

37.2

1212

9.6

0.26

3490

73.8

14.6

4.21

5.0

37.5

1502

6.8

0.18

3385

73.8

14.6

4.46

3.4

32.5

1229

0.27

3458

73.2

14.8

4.07

3.6

36.2

1316

6.7

0.20

3464

73.7

14.4

4.28

3.6

33.9

1186

8.7

0.24

3511

72.6

14.8

4.15

4.1

34.4

1270

7.4

0.19

3413

72.5

16.0

3.51

3.9

52.6

2010

2.3

0.03

3414

70.7

15.9

3.80

4.4

54.5

2165

1.5

0.02

3416

70.1

15.8

4.25

3.9

69.3

2021

2.2

0.04

3417

66.5

17.8

6.42

4.4

77.4

2754

2.8

0.05

3366

77.6

14.9

0.46

8.8

10.9

370

0.29

3387

81.8

13.2

0.32

7.6

7.8

0.36

Hora svaté Kate

iny

4471

76.6

12.2

5.56

2.5

31.7

390

1.44

4604

77.1

12.6

4.62

3.1

40.1

606

1.39

3097

74.2

13.2

4.58

3.7

38.3

1067

157

3.55

4554

75.5

12.6

4.36

3.4

37.7

1147

111

2.31

Teplice caldera
3194

76.1

12.3

5.13

1.6

20.9

393

1.97

3198

74.7

12.3

5.61

1.4

19.9

475

2.60

3201

76.4

12.3

5.42

1.1

18.1

246

1.26

3207

77.1

11.6

4.66

2.3

24.4

394

2.36

3208

76.4

11.8

6.32

1.4

20.3

248

0.80

3210

75.8

12.2

4.97

1.9

21.2

399

1.41

3211

61.4

24.4

0.91

2.3

32.4

0.98

3532

68.9

14.7

5.70

1.9

23.9

208

1.24

3376

68.1

14.7

5.88

1.7

23.7

182

1.25

4686

75.9

13.6

13.57

2.9

1393

1.06

4687

75.8

12.5

12.52

1390

131

4.38

4691

75.6

12.8

12.76

2.8

1133

114

3.94

4692

75.4

12.5

12.46

1.5

28.9

724

108

3.41

4693

75.5

12.6

12.55

1.7

32.4

802

103

3.44