ORES OF COPPER. 141 
‘This mineral receives a high polish and is used for tables, 
mante}pieces, vases; and also ear-rings, snuff-boxes, and va- 
rious ornamental articles. It is not much prized in jewelry. 
At Versailles there 1s a room furnished with tables, vases, 
and other articles of this kind ; and similar rooms are to be 
found in many European palaces. 
Malachite is sometimes passed off in jewelry as turquois, 
though easily distinguished by its shade of color and much 
inferior hardness. It is a valuabie ore when abundant ; but 
it is seldom smelted alone, because the metal is lable to es- 
cape with the liberated volatile ingredient. 
Azurite. —Blue Copper Carbonate. Blue Malachite. 
Monoclinic. In modified oblique rhombic prisms, the 
erystals rather short and stout ; 
lateral cleavage perfect. Also mas- 
sive. Often earthy. 
Color deep blue, azure blue, Ber- 
lin blue. ‘Transparent to nearly 
opaque. Streak bluish. Lustre 
vitreous, almost adamantine, Brit- 
tle. H.=3°5-45. G.=3'5-3°85. 
Composition. Cu, O,C,+ H, O= 
Carbon dioxide 25°6, copper oxide 
69°2, water 5:2. 3B.B. and in acids like the preceding. 
Obs. Azurite accompanies other ores of copper. Chessy, 
France, has afforded fine crystals ; found also in Siberia ; in 
the Banat; near Redruth in Cornwall; at Phoenixville, Pa., 
in crystals ; in Wisconsin near Mineral Point ; as incrusta- 
tions, and rarely as crystals, near Sing Sing, N. Y.; near 
New Brunswick, N. J.; near Nicholson’s Gap, in the Blue 
Ridge, Pa. 
When abundant it is a valuable ore of copper. It makes 
a poor pigment as it is liable to turn green. 
Aurichalcite (Buratite) is a hydrous copper-and-zine carbonate, or a 
cuprous hydrozincite, pale green to sky-blue in color ; from the Altai, 
Retzbanya, Chessy in France, Tyrol, Spain, Leadhills ‘in Scotland, and 
Lancaster, Pa. 

- Dioptase.—Copper Silicate. 
Rhombohedral. ARAR=126° 24’. Occurs in six-sided 
prisms with rhombohedral terminations. Color tmerald- 
ereen. Lustre vitreous. ‘Transparent to nearly opaque. 
Hid. G.= 3:28-3:35. 
