Vivianite - Huanuni Mine,Peru

Vivianite Crystal
Huanuni Mine, Huanuni, Dalance, Peru
single crystal : 34 x 20 x 9mm 
 
Vivianite is a hydrous Iron Phosphate from the weathered deposits at this mine, although many crystals of this quality have not been recovered from this locality for some years. It appears here as a glassy transparent crystal with amazing colour and lustre.
The crystal is a thin terminated sharply defined and quite gemmy bottle green prismatic and with some pleochroism, shifting from green to blueish depending on the light and viewing angle. Interesting bluish 'wisps' of pattern internally add yet another dimension.
 
please note Vivianite is one of many minerals that are light sensitive.