Actinolite Value, Price, and Jewelry Information

Actinolite is a member of a series that contains varying amounts of iron and magnesium. Tremolite is the Mg end, and ferroactinolite the Fe end, with actinolite in the middle. Actinolites with more than 50% Fe are very rare. Catseye actinolite exists (S.G. 3.0, R.I. 1.63); when chatoyant material is cut, it exhibits a fine eye. Actinolite is easy to cleave and hard to cut and would make a poor jewelry stone. Actinolite is the chief constituent of nephrite (jade). Smaragdite is a chrome-rich tremolite from Tanzania.

Actinolite Value

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Actinolite Value via Gem Price Guide

Cut	Weight	Price
Cat’s Eye	1 carat	/ct

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Actinolite Information

Data	Value
Name	Actinolite
Varieties	Smaragdite
Crystallography	Monoclinic; bladed crystals, usually elongated; fibrous, columnar aggregates. Also massive, granular, Often twinned.
Colors	Pale to dark green, blackish green, black.
Luster	Vitreous, sometimes dull.
Fracture	Uneven. Often fibrous nature. Brittle. Compact variety tough.
Hardness	5.5
Specific Gravity	Usually 3.05; Tanzania: 3.03-3.07; Max.: 3.44.
Birefringence	0.022-0.026.
Cleavage	2 directions good.
Stone Sizes	Actinolite is rarely facetable and usually in small fragments. Material from Chester, Vermont, could provide stones to about 10 carats. DG: 2.06 (greenish, step cut, Africa)
Luminescence	None (due to presence or Fe).
Spectral	Faint line at 5030.
Formula	Ca₂(Mg, Fe)₅Si₈O₂₂(OH)₂
Pleochroism	Yellow to dark green. Material transparent to nearly opaque. α: pale yellow/ yellowish-green. β: pale yellow-green/green. γ: pale green/ deep greenish blue.

Comments: Actinolite is a member of a series that contains varying amounts of iron and magnesium. Tremolite is the Mg end, and ferroactinolite the Fe end, with actinolite in the middle. Actinolites with more than 50% Fe are very rare. Catseye actinolite exists (S.G. 3.0, R.I. 1.63); when chatoyant material is cut, it exhibits a fine eye. Actinolite is easy to cleave and hard to cut and would make a poor jewelry stone. Actinolite is the chief constituent of nephrite (jade). Smaragdite is a chrome-rich tremolite from Tanzania.

Name: Greek aktis, meaning ray, due to the fibrous nature.

Optics:

α = 1.619-1.622;

β = 1.632-1.634;

γ = 1.642-1.644 (Tanzanian material).

Biaxial (-); 2V = 78°

Occurrence: Contact metamorphic limestones and dolomites; magnesium-rich limestones and ultrabasic rocks; regionally metamorphosed rocks.

Locality	Pleochroic Colors	α	β	γ	Birefringence	S.G.	Comments
Fowler, New York	red-violet	1.602	–	1.630	0.028	3.03	Hexagonite
Kenya	bright green	1.602	1.613	1.628	0.026	2.99	Tremolite
		1.607	1.618	1.632	0.025	3.01
Tanzania (Lelatema)	yellow green/green	1.608	1.616	1.631	0.023	3.01	Tremolite
Tanzania	emerald green	1.611	1.623	1.639	0.028	3.30	Tremolite + Cr
Tanzania (Merelani)	yellow-green/emerald green	1.608	1.618	1.63	0.022		Smaragdite
Taiwan	yellow-green/green tones,	1.607-	–	1.630-	0.023-	3.01	Tremolite
	also brownish	1.609		1.633	0.024
		1.615-	–	1.631-	0.014-	3.01	Catseye tremolite
		1.619		1.633	0.016
Uganda	yellow-green/green	1.619-	1.632-	1.642-	0.021-	3.04-	Tremolite-Actinolite
		1.622	1.634	1.644	0.024	3.07
	green/brown	1.633	–	1.653	0.020	3.15	Actinolite