Sylvanite

Description

Sylvanite has a hardness of 1.5-2 and a specific gravity of 8.2. It partially gets its name from an occurrence in Transylvania, but more so, because “Sylvanium” is an obsolete name for Tellurium, and this rock is comprised of around 60% Tellurium. It was first found in Baia de Arieș, Alba County, Romania, but it’s since been found in a few hundred additional localities worldwide, most commonly near low temperature hydrothermal veins and with many other nearby associated important ores.

Sylvanite is photosensitive and can accumulate a dark tarnish if it is exposed to bright light for too long, but it’s usually white, grey and/or gold colored, as well as sometimes purple, from the Tellurium. In addition to its 60% Te content, there’s also around 34% Gold and 6% Silver, so this makes for an awesome sample for element collectors looking for those three slightly more rare elements as they’re found in nature.

This specimen comes to us from the Tintic Mine near Eureka, Utah, but it’s found abundantly all over Colorado, and this specimen looks quite similar, but slightly different to the others listed on this channel from the Cresson Mine in Cripple Creek, but this is just a further testament as to the variation in appearances of gold-bearing minerals depending on where you are, so go take a hike and find some rocks that look like this!