Introduction: This mineral is normally white in colour, but varies to pale green or pale grey. Tremolite was first discovered in Val Tremola, near St Gotthard in Switzerland. It forms either elongate, bladed or fibrous columnar crystals.
Distribution: Found in the Windhoek district on farms Nauams 177 and Alberta 175. The farm 220 has tremolite in dolomite and giant tremolite crystals (20m long) occur in the Hakos Mountains 80km west of Rehoboth.
Composition: Silicate
Crystal system: Monoclinic
Lustre: Vitreous.
Streak: White
Hardness: 5-6