White radvaniceite fibres formed cotton-like aggregates in association with orange stangersite crystals; locality, Radvanice; field of view, 5 mm; photo, J. Sejkora. The image is published in an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( https://creativecommons.org/licenses/by/4.0/ ). — Photo: Jiří Sejkora · CC BY 4.0
Radvaniceite
Radvaniceite is an IMA-recognized mineral species in the sulfide class, with the chemical formula GeS₂.
It crystallizes in the monoclinic crystal system (space group Pc).
Key properties: specific gravity 2.99; White streak; Vitreous to adamantine luster.
IMA symbol Rad, IMA status: approved, named in 2021.
Found in a spontaneously burning coal mine dump. Formed under reducing conditions by direct crystallization from hot gasses (250-350 flC) containing Cl and F at a depth of 30-60 cm.
It is found associated with Stangersite, herzenbergite, greenockite, Bi-Sb solid solutions (site one); minerals of Bi-Sb, Bi2S3-Sb2S3 and Bi2S3-Bi2Se3 solid solutions, Bi3S2.
The name refers to the village near where the studied material was collected.