Formula: Ca₂(Fe²⁺)₅Si₈O₂₂(OH)₂
Mineral class: silicates
Crystal system: monoclinic
Mohs scale: 5 - 6
Density (g/cm³): 3.03 - 3.24
Refractive index: 1.614 - 1.653
Cleavage: good
Colors: green, black
Transparency: transparent - translucent
Luster: vitreous, silky
Fluorescence: -
Pleochroism: weak yellowish-greenish
Largest Actinolite crystal: 15 cm?
Deposits: worldwide
1st description: 1892
Name: from the Greek word "aktinos" (ray)

Actinolite Mineral

Size: 4.9 x 1.3 x 0.4 cm

Origin: Mogok / Sagaing Distr. / Mandalay / Myanmar

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Actinolite Mineral

Size: 6.4 x 4.0 x 1.9 cm

Origin: Otjiwarongo Distr. / Otjozondjupa / Namibia

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Actinolite Cat's Eye

Size: 1.43 x 1.38 x 0.95 cm
Weight: 15.24 ct
Origin: Russia

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Actinolite Cat's Eye

Size: 0.90 x 0.89 x 0.58 cm
Weight: 4.27 ct
Origin: Sri Lanka

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