Azurite with Chalcoalumite

Unknown Owner

This cabinet-sized display specimen is a true Bisbee classic and an attractive one at that. Royal blue velvety botryoidal Azurite coats Chalcoalumite as a peculiar layered stalactitic mottled pale turquoise blue to creamy-pale green phase lining a cavity within gossan. Chalcoalumite, an unusual copper aluminium sulphate hydroxide hydrate, was first described from Copper Queen mine at Bisbee in 1925, making this specimen from very near to, if not from, the Type Locality. Interestingly, it is now believed that all of the Chalcoalumite came from the Holbrook mine, or the Holbrook extension of the Lavender Pit at Bisbee. Either way, Chalcoalumite specimens from Bisbee are not easy to obtain, even as smaller specimens, and this one is large, colourful and full of the most amazing textures and form. Look carefully and the richness of the Chalcoalumite is staggering, extending right across the whole cavity underneath the Azurite. I can't prove it but the general classy appearance of this specimen suggests something with age to it. With a little more detailed research and specialist Bisbee knowledge the specifics of which mine, or pit this came from, and when, might be deciphered.