Kesterite (rare)

Item Description

This is a nice Kesterite from this iconic locality in China. Good crystallized Kesterites are rare worldwide, and certainly some of, if not THE finest examples have been found at the Pingwu Mine. The crystals are classic disphenoids, and are well isolated so they can be examined with ease. Overall, this is a great thumbnail of this exceptionally rare material, with smooth, well-formed faces, and only a few tiny nicks that can be seen when viewed up close. A very pale yellow-green coating of Mushistonite can be seen partially on select faces, and there is a TINY bit of acicular Malachite in one of the narrow crevices that I found with a loupe. A good piece of these well-known, yet rare and fine Kesterites.
From the collection of William ("Bill") (1927-2006) and Anne (1928-2021) Cook of Cleveland, Ohio (#13,127a) with a label from dealer Horst Burkard. 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. The rare barium lithium beryllium phosphate Wilancookite was named in their honor in 2015.