Occurs in incrustations and masses; color bluish-green; not fibrous; surface smooth; easily cut; does not effervesce in acid; blackens by heat; gravity 2.
Value.—An ore of copper, yielding thirty per cent.
Localities.—Found with other copper ores. Somerville and Schuyler’s, N. J.; Morgantown and Cornwall, Pa.; Wolcottville, Conn.; Big Williams’ Fork, Ariz.
62.—Silver.
Occurs in masses, or strings and threads penetrating rocks and native copper and galena; metallic lustre; tarnishes grayish black; can be cut in slices and hammered out; dissolved in muriatic acid, it turns black on exposure; gravity 10.
Localities.—Chiefly found with copper near trap-rocks, and in fine grained galena and dark brown blende. Gold contains from one to fifteen per cent. Bridgewater, N. J.; Davidson and Stanley Counties, N. C.; Lake Superior Region; Poorman’s Lode, Idaho; Comstock Lode and Montezuma Ledge, Nev.; Alpine County and Maris Vein, Cal.; Clear Creek County, Col.
63.—Silver Glance.
Occurs in small lumps, plates and threads; color dark gray; cuts like lead; melts in a candle giving off sulphur fumes; gravity 7.
Value.—The most important ore of silver, containing eighty-seven per cent.
Localities.—May be found almost everywhere, except in the coal regions; associated with other ores, quartz, limestone, baryta, etc. Most abundant where mineral veins cross one another. Comstock Lode, Gold Hill, Reese River, Cortez District and Silver-Sprout Vein, Nev.; Clear Creek County, Nev.