Chalcopyrite coated by Tetrahedrite

Item Description

A fine eye-catching specimen from the famed Naica Mine in Mexico. This locality is world-famous for its magnificent Gypsum crystals found in the Cave of the Crystals or Giant Crystal Cave, but Naica is also a well-known sulfide producer, and this piece is a great example of said material. This small cabinet display specimen features several very well-formed, sharp crystals of Chalcopyrite measuring up to 4.5 cm, which have a thin coating on the surface of dark grey Tetrahedrite. You can see tiny spots of the brassy hue of the Chalcopyrite poking through from underneath the Tetrahedrite, so you know it's just a coating, not a replacement/pseudomorph. Minor off-white Calcite can be seen as well for a nice touch of contrast. The piece is in good condition, with only a few spots of damage, but it displays beautifully and it actually sits nicely on its own without the aid of the base or clay. These are under-appreciated for what they are, certainly fine quality. You will rarely find pieces like this from Naica in the market these days, they really only exist in old comprehensive collections such as this one. Valued $950.
From the collection of William ("Bill") (1927-2006) and Anne (1928-2021) Cook of Cleveland, Ohio (#215). 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.