sideroplesIte

[Pref. sidero-, and Greek plēsios near.] Min.: A siderite (q. v.) containing much magnesia, and having specific gravity 3616 to 3.66. Formula, 2FeOCO2+MgOCO2. si-dër-o-schi-so-lite, s. [Pref. sidero-; Greek schistos split, and lithos =astone; Ger. sideroschiso lith.] Min.: A rhombohedral mineral, occurring in minute crystals, having a perfect basal cleavage. Hardne , 2.5; specific gravity, 3-3-4; luster, splen dent; color, velvet-black to dark-gray, opaque. An analysis yielded: Silica, 16'3; alumina, 4'1; pro to and sequioxides of iron, 75'5; water, 73 = 103°2, yielding the formula, 4FeO, SiO2+1/2 HO. Found in Brazil, with pyrrhotite, .