Pertoldite, trigonal GeO2, the germanium analog of α-quartz: a new mineral from Radvanice, Czech Republic

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F22%3A00128451" target="_blank" >RIV/00216224:14310/22:00128451 - isvavai.cz</a>

Result on the web

<a href="http://doi.org/10.3190/jgeosci.355" target="_blank" >http://doi.org/10.3190/jgeosci.355</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3190/jgeosci.355" target="_blank" >10.3190/jgeosci.355</a>

Result language

angličtina

Original language name

Pertoldite, trigonal GeO2, the germanium analog of α-quartz: a new mineral from Radvanice, Czech Republic

Original language description

The new mineral pertoldite was found in a burning waste dump of abandoned Katetina colliery at Radvanice near Trutnov, Hradec Kralove Department, Czech Republic. The dump fire started spontaneously before 1980 and no anthropogenic material was deposited there. The determination of pertoldite as a natural analogue of synthetic trigonal alpha-GeO2 is based on its chemical composition, X-ray powder diffraction data, and Raman spectroscopy. Pertoldite occurs as white to brownish aggregates resembling cotton tufts, up to 1 mm in size, composed of acicular crystals up to similar to 1 mu m thick and up to 1 mm in length. Individual crystals are distorted, resembling textile fibers. Pertoldite was fonned by direct crystallization from hot (400-500 degrees C) gasses containing Cl and F as transporting agents at a depth of 40-60 cm under the surface of a burning coal mine dump. It nucleated as a thin, delicate crust on a chip of siltstone together with multi-component aggregates of galena, stibnite, bismuthian antimony, greenockite, and bismuth. The ideal formula of pertoldite, GeO2, requires 100 wt. % GeO2. Germanium is partially substituted by silica (2.33-5.67 wt. % SiO2), the extent of Ge1Si-1 substitution is limited to 0.03-0.09 apfu Si, and the empirical formula ranges between (Ge0.91-0.97Si0.03-0.09)(Sigma 1.00)O-2. Pertoldite is trigonal, P3(1)21 or P3(2)21, a = 4.980(5) angstrom, c= 5.644(4) angstrom, with V= 121.2(2) angstrom(3) and Z = 3. The strongest reflections of the powder X-ray diffraction pattern [d (angstrom)/I (hkl)] are: 4.315/44(100), 3.425/100(101,011), 2.490/31(110), 2.360/41(012,102), 1.867/31(112), 1.4179/31(023,203), 1.4124/37 (122,212). The crystal structure of pertoldite is based on corner-sharing [GeO4] tetrahedra forming a three-dimensional network similar to that of alpha-quartz. Pertoldite is named after Zdenek Pertold (1933-2020), professor of economic geology at the Faculty of Sciences, Charles University in Prague. The mineral and its name have been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (number 2021-074) and the holotype specimen is deposited in the collections in the Department of Mineralogy and Petrology, National Museum in Prague, under the catalogue number PIP 31/2021.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10504 - Mineralogy

Project

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Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2022

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Journal of Geosciences

ISSN

1802-6222

e-ISSN

1803-1943

Volume of the periodical

67

Issue of the periodical within the volume

3

Country of publishing house

CZ - CZECH REPUBLIC

Number of pages

9

Pages from-to

229-237

UT code for WoS article

000891320300002

EID of the result in the Scopus database

2-s2.0-85142766182