feldspars
51Feldspar — Feld spar , Feldspath Feld spath , n. [G. feldspath; feld field + spath spar.] (Min.) A name given to a group of minerals, closely related in crystalline form, and all silicates of alumina with either potash, soda, lime, or, in one case, baryta.… …
52Feldspath — Feldspar Feld spar , Feldspath Feld spath , n. [G. feldspath; feld field + spath spar.] (Min.) A name given to a group of minerals, closely related in crystalline form, and all silicates of alumina with either potash, soda, lime, or, in one case …
53Orthoclastic — Or tho*clas tic, a. (Crystallog.) Breaking in directions at right angles to each other; said of the monoclinic feldspars. [1913 Webster] …
54Polysynthetic twinning — Twinning Twin ning, n. (Crystallog.) The assemblage of two or more crystals, or parts of crystals, in reversed position with reference to each other in accordance with some definite law; also, rarely, in artificial twinning (accomplished for… …
55Repeated twinning — Twinning Twin ning, n. (Crystallog.) The assemblage of two or more crystals, or parts of crystals, in reversed position with reference to each other in accordance with some definite law; also, rarely, in artificial twinning (accomplished for… …
56Twinning — Twin ning, n. (Crystallog.) The assemblage of two or more crystals, or parts of crystals, in reversed position with reference to each other in accordance with some definite law; also, rarely, in artificial twinning (accomplished for example by… …
57Twinning axis — Twinning Twin ning, n. (Crystallog.) The assemblage of two or more crystals, or parts of crystals, in reversed position with reference to each other in accordance with some definite law; also, rarely, in artificial twinning (accomplished for… …
58Twinning plane — Twinning Twin ning, n. (Crystallog.) The assemblage of two or more crystals, or parts of crystals, in reversed position with reference to each other in accordance with some definite law; also, rarely, in artificial twinning (accomplished for… …
59zeolite — noun Etymology: Swedish zeolit, from Greek zein to boil + o + Swedish lit lite, from French lite more at yeast Date: circa 1777 any of various hydrous silicates that are analogous in composition to the feldspars, occur as secondary minerals in… …
60Amblygonite — General Category Phosphate minerals Chemical formula (Li …