noun
definition
A mineral with monoclinic crystals of the chemical formula Ca2(Mg,Fe)5Si8O22(OH)2, belonging to the amphibole group.
Examples of actinolite in a Sentence
They are soft and lustrous, with a peculiarly smooth feel, and though often confounded with mica-schists may be distinguished by their richness in magnesia; many of them contain tremolite or actinolite; others have residual grains of olivine or augite; and here also every gradation can be found between the unmodified igneous types and the perfectly metamorphic schists.
From these rocks in the Ottawa valley are quarried or mined granite, marble, magnificent blue sodalite, felspar, talc, actinolite, mica, apatite, graphite and corundum; the latter mineral, which occurs on a larger scale here than elsewhere, is rapidly replacing emery as an abrasive.
Enclosures of other minerals (rutile, chlorite, haematite, gothite, actinolite, asbestos and many others) are extremely frequent in crystals of quartz.
The six types of asbestos are chrysotile, crocidolite, amosite, anthophyllite asbestos, tremolite asbestos, and actinolite asbestos.