释义 |
fluor-spar Min.|ˈfluːəspɑː(r)| [f. fluor + spar.] Native fluoride of calcium (Ca F2); found abundantly in Derbyshire (where one variety is known as Blue John), and hence often called Derbyshire spar.
1794Kirwan Min. I. 127, 3d Family, Foliated or sparry, Fluor spar. 1812Sir H. Davy Chem. Philos. 465 A substance found abundantly in nature called fluor spar, it is usually either blue, green, yellow, or white, transparent, and crystallized in cubes. 1880Ansted Minerals 18 The crystal of fluor-spar has the striæ parallel all round the four sides. |