Calcite pseudomorph after Ikaite ("Glendonite") (RARE locality specimen) (ex Kay Robertson Collection)

Item Description

This is the first specimen we've ever seen labeled as coming from Codroy, which is a community in the Codroy Valley of Newfoundland, Canada. If you're a fan of pseudomorphs, this is one of those "never going to see another one of these" moments. This attractive toenail specimen is a fine example of what you might see labeled as "Glendonite" in the mineral world, but they are pseudomorphs of what began as the hydrated calcium carbonate species Ikaite and later changed into Calcite. Ikaite loses its water molecules above 8 °C (46 °F) and becomes Calcite, but it still retains the original monoclinic shape of the Ikaite crystals. This piece hosts several very sharp, well-formed, pointed pyramidal crystals with a soft milky white hue on the exterior measuring up to 1.7 cm long and free of matrix. The piece is complete all around and I can't find any real damage of note. A super interesting piece from the far southwestern tip of Newfoundland. Ex Kay Robertson Collection (#11316). Kay was a prominent California collector, who specialized in European classics. She nearly lived 100 years from April 1920 - March 2020. See the article in the March-April, 2007 Mineralogical Record ( https://www.mineralogicalrecord.com/pdfs/Kay%20Robertson%20Collection.pdf ), and the 50+ page article in the German Magazine "Mineralien Welt" November-December 2017.