*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. They occur in crystals and crystalline masses, vitreous in luster, and breaking rather easily in two directions at right angles to each other, or nearly so. The colors are usually white or nearly white, flesh-red, bluish, or greenish. [ 1913 Webster ]

☞ The group includes the monoclinic (orthoclastic) species orthoclase or common potash feldspar, and the rare hyalophane or baryta feldspar; also the triclinic species (called in general plagioclase) microcline, like orthoclase a potash feldspar; anorthite or lime feldspar; albite or soda feldspar; also intermediate between the last two species, labradorite, andesine, oligoclase, containing both lime and soda in varying amounts. The feldspars are essential constituents of nearly all crystalline rocks, as granite, gneiss, mica, slate, most kinds of basalt and trachyte, etc. The decomposition of feldspar has yielded a large part of the clay of the soil, also the mineral kaolin, an essential material in the making of fine pottery. Common feldspar is itself largely used for the same purpose.

{ , a. Pertaining to, or consisting of, feldspar. [ 1913 Webster ]

{ , n. (Min.) See Feldspar. [ 1913 Webster ]

a. See Feldspathic. [ 1913 Webster ]

‖n.; pl. Spathae [ L. ] (Bot.) A spathe. [ 1913 Webster ]

a. (Bot.) Having a spathe; resembling a spathe; spathal. [ 1913 Webster ]

a. (Bot.) Furnished with a spathe; as, spathal flowers. Howitt. [ 1913 Webster ]

n. [ L. spatha, Gr. &unr_;: cf. F. spathe. See Spade for digging. ] (Bot.) A special involucre formed of one leaf and inclosing a spadix, as in aroid plants and palms. See the Note under Bract, and Illust. of Spadix. [ 1913 Webster ]

☞ The name is also given to the several-leaved involucre of the iris and other similar plants. [ 1913 Webster ]

a. (Bot.) Having a spathe or calyx like a sheath. [ 1913 Webster ]

a. [ Cf. F. spathique, fr. F. & G. spath spar. ] Like spar; foliated or lamellar; spathose. [ 1913 Webster ]

Spathic iron (Min.), siderite. See Siderite (a). [ 1913 Webster ]

a. [ F. spathiforme. ] Resembling spar in form. “The ocherous, spathiform, and mineralized forms of uranite.” Lavoisier (Trans.). [ 1913 Webster ]

a. (Min.) See Spathic. [ 1913 Webster ]

a. [ See Spathe. ] (Bot.) Having a spathe; resembling a spathe; spatheceous; spathal. [ 1913 Webster ]

a. (Bot.) Spathose. [ 1913 Webster ]