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METALLIFEROUS MINERALS. 373 in Sweden, Ratieborzilz in Bohemia, and several of the kaxon localities, are celebrated for the splendid brown and black crystals which they afford. {Manual.) Cadmiferous Blende. The splendent fibrous blende of Przi- h'am possesses a lustre very nearly metallic, especially after * r esh fracture; its structure is radiated, the fibres are shining, and of a brown colour, and it contains a small proportion of cadmium. A white fibrous variety in botryoidal concretions also occurs in Fowey consolidated mines ; the massive in many other Cornish localities. Though this ore is frequently found in large quantities, the difficulty of reducing it, and the limited extent to which it can consequently be applied, render it a production of little impor tance ; it is however in some instances employed as an ore of zinc. RED OXIDE OF ZINC. Ifismalic Zinc Ore, M. Zink Oxyd, L. Zinc OxyiW Manganesifere, B. Oxide of zinc, usually mixed with red oxide of manganese. New Jersey. Oxide of zinc 92-0 88'0 Oxide of iron and manganese 8'0 12 - 0 Bruce. Berth ier. Sp. Gr. 5-4—5-5. II. = 4 0—4 5. Colour aurora- or vermilion-red, inclining to yellow. Primary onn a right rhombic prism of about 125° and 55°. It occurs , )r ? SSl . Ve ’ disseminated, and micaceous ; the structure is lamellar; * Ul cipal cleavage parallel to the terminal plane of the prism; anslucent when reduced to thin laminae, or opake; with anada- a ntinc or shining lustre ; but on exposure it becomes dull and t 7«cd by a pearly crust; streak orange-yellow; fracture con- sihl f 1 ’ 1)rittle > a,| d easily scratched by the knife. It is infu- coaf ■ ore tlle blowpipe without addition, covering the char- ' v itl ?“ h Z ' nc ^' u mes when exposed to the reducing flame ; but °f nl ax me fts into a transparent yellow bead, and with salt f'erv ’ 0s l >,loru8 forms a colourless one. It is soluble without ef- 1 om C f Cence in nitric ocid, and is supposed to derive its red co- ^ rout the manganese it contains, calc ° ccurs O'ussive, and in considerable quantities, mixed with n eat . S P ar ai, d franklinitc, at the F'ranklin and Stirling mines mj n l )a f ta in New Jersey. Mitscherlich lias described some of 0 six-sided prisms, formed artificially in the iron furnaces •i»ccie n,6 * 1,aUC * n ^ es ' n > "’1'ich he believes to belong to this