Brassite pseudomorph after Rösslerite with Pharmacolite (INCREDIBLY rare) (ex Dr. Wouter van Tichelen Collection)

Item Description

A ridiculously rare specimen from the famous, historic Svornost Mine at Jáchymov in the Czech Republic. This cabinet sized piece features chalky white pseudomorphs of Brassite which have replaced Rösslerite, and are associated with translucent, colorless prismatic "sprays" of Pharmacolite on matrix. Brassite is a very rare hydrated Mg-arsenate and Jachymov is the type locality for the species. These pseudomorphs are virtually impossible to find these days, but the Pharmacolite association is SIGNIFICANT because they're actually crystallized(!), and this is literally THE FIRST AND ONLY specimen we've had to offer from this locality that features Pharmacolite. I can't even find another photo of the species from the Svornost Mine on mindat.org, which is really saying something. A must-have specimen for any fan of old-time European localities, rare pseudomorphs or specifically minerals from the Czech Republic. From the prestigious pseudomorph collection of Dr. Wouter van Tichelen of Belgium, with an additional label from noted Czech / Slovak mineral expert, Josef Vajdak, which immediately increases the value in my opinion.