Crystals can be similar to hornblende, but are always translucent or even transparent. Typically they are prismatic, flattened and elongated. Crystal specimens of actinolite can make very interesting mineral specimens. Color is usually green.white or gray. Luster is vitreous.
Fracture is splintery to uneven.
Hardness is 5.5 - 6. Streak is white. Associated Minerals are quartz , lawsaonite , epidote and glaucophane .