Santabarbaraite pseudomorph after Vivianite on mollusk shell (ex Dr. Wouter van Tichelen Collection)

Item Description

A superb quality and very eye-catching specimen of the famous, and now very hard to find pseudomorphs of Santabarbaraite pseudomorphing after preexisting Vivianite crystals on a fossil mollusk shell. Vivianite is an iron phosphate with 8 water molecules in its chemical composition, and Santabarbaraite is also an iron phosphate, but only has five water molecules along with three hydroxyl molecules. Essentially three of the original water molecules from the Vivianite lose a hydrogen atom, turn into a hydroxyl, and Vivianite changes to Santabarbaraite. This piece features superb quality, rusty colored blades and "sprays" of Santabarbaraite, which are some of the finest I've seen from the Kamysh-Burun Trough. Additionally, the fossil mollusk shell upon which the Santabarbaraite sits is one of the best, most complete and well-formed shells that I've seen from the locality as well. Priced at $900 for superior quality all around. From the noted pseudomorph collection of Dr. Wouter van Tichelen of Belgium.