Santabararaite is a rare and interesting mineral species. Amorphous in structure it always takes on the form (pseudomorphous) of the mineral which it has replaced - in this case bladed Vivianite - but with its own distinctive colour. Chemically, compared with Vivianite, it is a lesser hydrate, meaning that it forms naturally through the dehydration of Vivianite, but the conditions have to be just right for Santabarbaite to stabilize rather than a more common alteration product. The Kerchenskoe deposit, Kerch Peninsula, Crimea is one of the few places in the world where large bladed Santabarbarite pseudomorphs after Vivianite occur. Although small miniature to very large toenail in size, this fine specimen features crystals to 2 cm in length presenting the distinctive rich orange-brown Santabarbaraite colour. It is from the superb systematic collection assembled by the brothers Martin and Michael Günther (1951-2007 & 1956-2021).
