Vivianite - Brazil (w/ stand)Vivianite is a rare mineral known for changing from a colorless to a saturated blue green. Light exposure causes internal oxidation, causing the permanent color change. It is a fragile mineral making it rare to find in jewelry or in faceted form. The natural crystals are prismatic, or tabular, growing in bladed groups of crystal clusters. It was discovered in the Wheal Kine mine in Cornwall, England, and named by the German geologist Abraham Gottlob