amphibole
/ˈæm.fɪˌboʊl/ noun
Forms amphiboles
- noun (mineralogy) Any of a large group of structurally similar hydrated double silicate minerals, containing various combinations of sodium, calcium, magnesium, iron, and aluminium.
Etymology
From French amphibole, coined by René Just Haüy from Ancient Greek ἀμφίβολος (amphíbolos, “ambiguous”), in reference to its many forms.
Webster’s 1913
- noun A common mineral embracing many varieties varying in color and in composition. It occurs in monoclinic crystals; also massive, generally with fibrous or columnar structure. The color varies from white to gray, green, brown, and black. It is a silicate of magnesium and calcium, with usually aluminium and iron. Some common varieties are tremolite, actinolite, asbestus, edenite, hornblende (the last name being also used as a general term for the whole species).
Etymology [Gr. amphibole. Haüy so named the genus from the great variety of color and composition assumed by the mineral.]
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “amphibole”, CC BY-SA 4.0. Details