Huanuni Mine, Huanuni, Dalence Province, Oruro Department, Bolivia
A unique gem crystal of vivianite has a modified monoclinic form. While areas show the classic wedge or sword form, it appears almost as if it was pressed and bent while still hot. These areas have duller luster than the adjacent areas with very high luster. Dark in ambient light. But it takes directed light easily and shows that it is gemmy with a deep emerald color edged by navy blue. When vivianite is found, it is usually colorless but changes to the deep colors when oxygen in the atmosphere converts Fe2+ to Fe3+ which acts as a coloring agent.
5.70 x 5.00 x 1.50 cm