Hackmanite (UV) - 10 poundsLocality: Sar e Sang, Afghanistan Hackmanite is a fascinating mineral primarily known for its unique property of tenebrescence, which means it can change color when exposed to different types of light. Color: Hackmanite typically appears as a grayish white or colorless mineral in its natural state. However, when exposed to UV light (particularly longwave UV), it can exhibit a remarkable color change, usually transforming into shades of pink, purple,