The first metal that was employed by man is copper. It is probable that prehistoric man made use of the metal in its native condition only, as no knowledge of metallurgy would be essential in preparing it for use from that condition. Copper implements have been found in the lake dwellings of Switzerland, and bronze, an alloy of copper and tin, is mentioned in the writings of Homeric times. Cuprum, the origin of our English word copper, is derived from cyprium, which refers to the occurrence of the metal in especial abundance on the island of Cyprus, the main source of the metal during the epochs of early alchemy. In the Hebrew scriptures copper is termed Nehósheth (from nahásh, meaning to glisten) which is translated by Χαλκος and by Aes in the Vulgate. Later _Aes cyprium_ was the special designation, which was finally shortened to _cyprium_, as indicated above. Thus we see that our present term represents in no sense the characteristic of the metal at first so noticeable. Native copper scarcely needs a description. Its occurrence in the free state provides an interesting subject of conjecture. Briefly stated, the question of origin is whether the copper was set free by the decomposition of silicates or was in the form of a sulphide in the rock. The chief region of occurrence of native copper is the Lake Superior district. Here are found occasionally large masses of copper, which, strange as it seems, are practically valueless if too heavy to transport, since they cannot be divided without great difficulty. Of the world's total output of copper in 1897, 399,250 long tons[2], a single mine of the Lake Superior region, the famous Calumet and Hecla, produced 40,350 long tons. Montana is now the first copper producing state in the United States. The state contains the largest mining camp in the world, located in the town of Butte. In 1897 the mines of Montana produced 102,800 long tons of copper. The ore chalcocite, sometimes called copper glance, has a metallic luster, often tarnished green or blue. It is commonly lead-gray and rather soft. Its streak is a blackish lead-gray, Chalcopyrite, a sulphide of copper and iron combined, has already been mentioned under "Iron Minerals" (November issue of BIRDS AND ALL NATURE.) When copper is much in predominance the color of the ore is golden yellow. The streak is dark green. The mineral is harder than chalcocite, but less hard than pyrite, being easily scratched with a knife. Both chalcocite and chalcopyrite frequently occur in silver-bearing rocks.