- A monoclinic-prismatic mineral containing hydrogen, metal, magnesium, manganese, air, and phosphorus.
- A mineral occurring in tiny, green, clear, monoclinic crystals. It really is a hydrous phosphate of iron.
- A hydrous phosphate of metal, happening in bright-green monoclinic crystals. It is found near Truro in Cornwall, and it is of vivianite in cavities in pyrite.