Blue Quartz pseudomorph after Calcite (unique specimen)

Item Description

A really special, unique and eye-catching specimen from Iraí in the southern state of Rio Grande do Sul, Brazil. This area is best known for its beautiful Amethyst and Calcite specimens, but this piece is notably different as it features stark blue colored massive Quartz which have pseudomorphed after "dogtooth"-shaped crystals of Calcite. I've seen Quartz pseudomorphs after Anhydrite from this area, but I can't recall a single Quartz after Calcite, especially one with a RARE BLUE color like this. Quartz is found in a wide range of hues, but blue is incredibly hard to find, to have such a scarce hue replacing Calcite like this is incredible. The largest crystal on the piece measures 3.2 cm long. Most of the crystals are in good shape, only minor roughness, and the original form of the Calcites are beautifully well-preserved with defined, sharp, smooth faces. Don't miss out on this one if you're a pseudomorph collector, it's the only one we've ever seen and I highly doubt we'll have another like it anytime soon. It's the kind unique specimen that you would expect to see in such a renowned Brazilian collection. It's impossible to place a fair market value on such a singular piece, but I value it highly for it's beauty and rarity.
From the collection of the recently deceased Alvaro Lucio, arguably the most well-known and accomplished mineral dealer and collector in Brazil. Alvaro graduated with a degree in civil engineering, mining and metallurgy from the Escola de Minas de Ouro Preto in 1949. He began his PhD in the United States and completed it at the Federal University of Minas Gerais. He worked as a professor of extractive metallurgy at UFMG, and also as a technical consultant for several companies in the sector. He was the author of several works, published in books and magazines around the world. He received several honors for his contribution to the development of metallurgy and the introduction of metallurgical physical chemistry in Brazil. His knowledge, solicitousness and enthusiasm will be greatly missed in the mineral world.