Actinolite

1. A metamorphic ferromagnesian mineral; an asbestos.
   Source: Leet, L. Don. 1982. Physical Geology, 6th Edition. Englewood Cliffs, NJ: Prentice-Hall
2. A monoclinic mineral, 2[Ca2 (Mg,Fe)5 Si8 O22 (OH)2 ] in the hornblende series Mg/(Mg+Fe2+ ) = 0.5 to 0.89 of the amphibole group; forms a series with tremolite; green, bladed, acicular, fibrous (byssolite asbestos), or massive (nephrite jade); prismatic cleavage; in low-grade metamorphic rocks. Syn: actinote; strahlite. CF: tremolite
   Source: Dictionary of Mining, Mineral, and Related Terms