RATHITE, DUFRENOYSITE, REALGAR (miniature)

A very rare and older specimen from the Lengenbach Quarry.

Microscopic research reveals this specimen might contain

Rathite is an exceptionally rare mineral classified within the "sulfides and sulfosalts" category, characterized by its complex chemical formula Ag2Pb12−xTlx/2As18+x/2S40, making it a silver thallium sulfarsenide. This mineral crystallizes in the monoclinic system, forming large, prismatic crystals that exhibit a metallic luster, reminiscent of sartorite. Typically lead-gray in color, rathite can develop an iridescent tarnish and appears greyish white with deep red reflections under incident light, while its streak is a distinctive chocolate brown. Rathite was first identified in mineral samples from the Lengenbach pit in the Binn Valley of Switzerland's Valais canton, with its analysis and initial description conducted by Heinrich Adolph Baumhauer in 1896, who named the mineral in honor of his professor, Gerhard vom Rath.

Dufrénoysite was first identified in the Lengenbach pit located in the Binn Valley of Switzerland's Valais canton. The mineral was described in 1845 by Augustin Alexis Damour, who named it in honor of the French geologist and mineralogist Armand Dufrénoy. In 1864, Julius Berendes further explored the properties of this mineral in his dissertation.