Tennantite Subgroup pseudomorph after Azurite with Cerussite

Item Description

These pseudomorphs are personal favorites of mine, and they are certainly distinctive and unique to Tsumeb to the best of my knowledge. Consider for a moment the rarity of a specimen where a copper sulfosalt (which usually forms earlier in the paragenesis) replaces a secondary copper carbonate that was derived from native copper to begin with. Tsumeb has a wide array of pseudomorphs, but these pieces are truly special. This attractive cabinet features a very good sized, attractive, pseudomorph of Tennantite (technically the Tennantite Subgroup) after Azurite, free of matrix. The icing on the cake is that there are some beautiful, sharp, lustrous, gemmy, golden-smoky colored reticulated "snowflake"-shaped group of Cerussite at the base of the piece(!), which is very rarely seen in this material. While the overall form of the pseudomorph is a bit distorted, there is no real damage that I can see with the naked eye. A truly beautiful, large example of this classic material. This piece dates back to the 1970s era of mining at Tsumeb, and if I had it for sale at a show, I would put it in the range of about $5,000 retail.
From the collection Dr. Robert ("Rob") Bowell, a geochemist and adjunct professor in Geochemistry and Mineralogy at Queen's University, Kingston, Ontario, Canada. Rob has a background in applied geology in tropical and deeply weathered terrains, he also has done mining consulting in the fields of due diligence, financial and technical audits, process chemistry, environmental geochemistry, environmental engineering and mineralogy.