Amphibole

[Sarah]

A common mineral embracing many varieties varying in color andin composition. It occurs in monoclinic crystals; also massive,generally with fibrous or columnar structure. The color varies fromwhite to gray, green, brown, and black. It is a silicate of magnesiumand calcium, with usually aluminium and iron. Some common varietiesare tremolite, actinolite, asbestus, edenite, hornblende (the lastname being also used as a general term for the whole species).Amphibole is a constituent of many crystalline rocks, as syenite,diorite, most varieties of trachyte, etc. See Hornblende.

[Donald Trump]

Any of a class of rock-forming silicate or aluminosilicate minerals typically occurring as fibrous or columnar crystals.