Sturmanite coating Ettringite

Item Description

A fine thumbnail specimen from the N'Chwaning Mines in South Africa featuring dark golden colored Sturmanite overgrowing more yellow colored Ettringite. The piece shows excellent, sharp, well-formed, hexagonal faces, with no damage, save the bottom where it was removed from the pocket wall. An attractive and fine quality example of this rare material. A must have for any fan of minerals from the Kalahari Manganese Field, or any thumbnail collector. From the collection of William ("Bill") (1927-2006) and Anne (1928-2021) Cook of Cleveland, Ohio (#3631). This husband and wife duo were actively involved in the mineral world for many decades. Bill was a PhD geologist, and Anne was a mathematician, and they both were very serious mineral collectors. Bill served for many years as adjunct curator of mineralogy at the Cleveland Museum of Natural History, and Anne was inducted into the Micromounters' Hall of Fame on October 12, 2019. Both Bill and Anne, at various times, served as president both of the Mineralogical Society of Cleveland and of the Micromineral Society of the Cleveland Museum of Natural History, and Anne was inducted into the mi The rare barium lithium beryllium phosphate Wilancookite was named in their honor in 2015.