Description

A respectable-sized specimen containing at least four mineral species: argentite, chloanthite (or smaltine), annabergite and erythrite.
These minerals were discovered at the Chalanches mine in Allemont, Oisans, Isère.
Its two polished faces reveal a beautiful brilliance.
A specimen discovered in the 19th century, or even the 18th, it comes from the collections of the Petit Séminaire de Grenoble in Isère, as well as from the collection of Eric Asselborn.
This association is a great French mineralogical rarity from the Chalanches mine in Oisans (Isère).
In this deposit, antimony oxide was first identified in 1783 by Mongez, and named valentinite, along with a peculiar association of two substances: a mineral, stibarsen (hexagonal AsSb) and a native element, antimony.
This association is called allemontite, after the village of Allemont in the valley.
Here’s a video of this mineral specimen from Chalanches:

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