Actinolite
Actinolite | ||
---|---|---|
2V angle 78–82° (calc), 84–73° (meas) | | |
Dispersion | r < v | |
Ultraviolet fluorescence | inert | |
Absorption spectra | faint line at 503 nm | |
References | [2][3][4][5][6] |
Actinolite is an
Etymology
The name actinolite is derived from the Greek word aktis (ἀκτίς), meaning "beam" or "ray", because of the mineral's fibrous nature.[3]
Mineralogy
Actinolite is an intermediate member in a solid-solution series between magnesium-rich tremolite, Ca2(Mg5.0-4.5Fe2+0.0-0.5)Si8O22(OH)2, and iron-rich ferro-actinolite, ☐Ca2(Mg2.5-0.0Fe2+2.5-5.0)Si8O22(OH)2. Mg and Fe ions can be freely exchanged in the crystal structure. Like tremolite, asbestiform actinolite is regulated as asbestos.
Occurrence
Actinolite is commonly found in
The old mineral name uralite is at times applied to an alteration product of primary
Fibrous actinolite is one of the six recognised types of
Gemology
Some forms of actinolite are used as gemstones. One is nephrite, one of the two types of jade (the other being jadeite, a variety of pyroxene).[5]
Another gem variety is the
See also
- Classification of minerals
- List of minerals
References
- S2CID 235729616.
- ^ Actinolite. Mindat.org
- ^ a b Actinolite. Webmineral.org
- ^ Actinolite. Handbook of mineralogy
- ^ ISBN 0-87311-019-6
- ^ IMA Master List
- Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., John Wiley and Sons, New York ISBN 0-471-80580-7