520 ' NICKEL. most generally associated are nickel-ochre, tin-white and silver white cobalt-ores, ores of copper, and of silver, along with calcareous-spar, brown-spar, heavy-spar, and quartz. Geographic Situation. Europe.—It occurs in small quantity in the lead-mines of Lead Hills and VVanlockhead ; also in veins along with nickel ochre, galena or lead-glance, brown-blende, and heavy spar, in a bed of limestone in the coal field of Lin lithgowshire *. On the Continent, it occurs in veins in primitive rocks at Schneeberg and Johanngeorgenstadt in Saxony; at Joachimsthal in Bohemia; at Schladring in Upper Stiria; and Allemont in France. It is found fn a bed along with native gold and ores of cobalt and cop per. in porpbyritic syenite, at Cravicza in the Bannat. It is met with in veins that traverse transition rocks at Andreasberg in the Ilartz. In the county of Mansfeldt, it occurs in veins that traverse bituminous marl-slate. It is also found at W.ttichen in Swabia ; Salzburg, and Gis- tain in Arragon in Spain. Asia.—Koliwan in Siberia. Observations. It very nearly resembles native copper, but its brittle ness very readily distinguishes it from that mineral. 3. Black * Vid. Dr Fleming, in AnnaU of Philosophy.