from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A greenish variety of amphibole.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A mineral with monoclinic crystals of the chemical formula Ca2(Mg,Fe)5Si8O22(OH)2, belonging to the amphibole group.
from the GNU version of the Collaborative International Dictionary of English
- n. A bright green variety of amphibole occurring usually in fibrous or columnar masses.
from The Century Dictionary and Cyclopedia
- n. A radiatedmineral, called by Werner strahlstein (ray-stone), consisting of silicates of calcium, magnesium, and iron.
- n. A trade-name of an apparatus by which the ultra-violet rays may be employed in the treatment of cutaneous diseases.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a green mineral of the amphibole group; calcium magnesium iron silicate
Sorry, no etymologies found.
In accompanying notes, a geologist identified as W.J. Hunter boasted of a rock formation from the Miocene Epoch that gleamed with boulders of "tourmaline-actinolite-quartz plutonites."
Greenstone, diorite, and actinolite are found, though not so abundantly as those above mentioned.
In particular, the minerals concerned are: chrysotile, amosite, crocidolite, anthophyllite, tremolite und actinolite, which are categorized on the basis of their chemical composition and fibrous structure as serpentine Asbestos
The general character of the rock here is sienitic; but, besides this peculiar quality of feldspar, the hornblende appears as actinolite, (ray-stone,) so called from the form of its crystallization; while the quartz element is faintly present, or appears in separate masses.
_Chalcedony_ too (which when banded furnishes us our _agates_, and when reddish our _carnelian_) is a variety of quartz, and _prase_ is only quartz colored green by fibers of actinolite within it.
These include a dangerous fibrous asbestos as well as the harmless monoclinic amphibole, actinolite: two minerals with the same composition but very different effects on human physiology.
The six types of asbestos are chrysotile, crocidolite, amosite, anthophyllite asbestos, tremolite asbestos, and actinolite asbestos.
Libby vermiculite is contaminated with an especially toxic form of naturally-occurring asbestos called tremolite-actinolite asbestiform mineral fibers.
South - west of this, five miles above Catar6 to the west of the road, and northwest of Mount Basimo, he obtained a dark-colored actinolite slate.
The types amosite, anthopyllite, tremolite and actinolite are quantitatively (together 50 000