Named after the English mineralogist, F. G. Vivian, this rare mineral of secondary origin exhibits an intense dark blue masstone with a slight reddish blue undertone. Vivianite has been identified in medieval paintings in Germany and in English medieval polychromy. The school of Cologne used it to depict skies in the 13th and 14th century.
- ASTM Lightfastness Rating: Excellent
- Tranparency: Transparent
- Staining: Non-staining
- Granulating: Yes