Actinolite, Selavastn.

Actinolite, Selavastn.

Actinolite is a highly complex silicate, asbestos mineral with a formula too complicated for this short note. The specimen is from the contact zone between carbonate rock and a hydrothermal quartz body, at Selasvatn in the region of vegarshei, Aust-Agder, in Norway. In the specimen, dark green Actinolite is in the asbestiform habit of long, thin fibrous crystals. A higher presence of iron correlates with a deeper green colour.