Tennantite Subgroup

This specimen features a single, sharp black tetrahedral crystal of tennantite, well-formed, but not whole as it shows contact at the back where it was once attached to matrix. The crystal is notably large for the species, making this an exceptional thumbnail and an immediately eye-catching example of this important sulfosalt mineral.

For many years, tennantite was treated as a single mineral species, but modern mineralogical work has since divided it into a subgroup comprising several distinct species, including Tennantite-(Cu), -(Fe), -(Zn), -(Cd), -(Hg), and -(Ni). As the specific dominant metal has not been analytically determined for this crystal, it is most accurately labeled as belonging to the Tennantite Subgroup.

Well-formed tennantite crystals of this size and quality are uncommon from any locality, and even at Tsumeb they are decidedly scarce. This specimen represents older material from the renowned Tsumeb Mine, likely dating to the 1960s–1970s period of mining, when some of the finest sulfosalt specimens were recovered.

Tsumeb has long been regarded as one of the world’s premier localities for tennantite, producing crystals that are unmatched in sharpness, form, and overall quality. This crystal stands as an excellent representative of that legacy and is a fine example of a comparatively rare ore mineral.