Vivianite, Blue-green cluster, Brazil 244g

CW18

5" x 2.39" x 1.16"

Bin B

Vivianite is a hydrated iron phosphate mineral that often forms inside fossil shells, bones, or organic-rich clays. When freshly mined, it’s usually colorless to pale green — but when exposed to light and air, it oxidizes and deepens into striking shades of blue, green, or deep indigo. This natural transformation is part of what makes Vivianite so intriguing