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NICKEL. 
Cases G and I. — A complete series showing ores of nickel, 
processes of extraction and applications of the metal, presented 
by the American Nickel Works of Camden, N. J. Note as the 
principal ores, the bronze colored sulphide, pyrrhotite, the brass 
colored sulphide, frequently in capillary forms, millerite and the 
apple green silicate, garnierite. 
Nickel ores from Canada, Oregon and New Granada. A chart 
near by gives the process of extraction of nickel from the Cana- 
dian pvrrhotite. As uses of the metal, are shown specimens of 
plating, nickel steel alloy for armor, salts of use in the arts, etc. 
ALUMINUn. 
Case I.— Ores and products of aluminum. Though alu- 
minum is the metal contained in common clay, efforts to extract it 
cheaply from this substance have so far failed. 
The ores from which it is obtained -bauxite and cryolite- 
are shown in the case, together with sheets of the metal and speci- 
mens of its alloys. 
Case K.— Type specimens of iron ores. These are:— the 
black oxide, magnetite 72 percent, iron; the red oxide, hematite , 
70 per cent, iron; the hydrous oxides, turgite , 66 percent, iron; 
g’othite , 64 per cent, iron; and limonite , 60 per cent, iron; the car- 
bonate, siderite , 48 per cent. iron. Many varieties of these ores are 
shown, which are known by the names of yellow ochre , bog ore , 
pipe ore and. brown hematite i forms of limonite, red ochre , specu- 
lar , micaceous , needle and kidney ores , forms of hematite; clay iron 
stone , black band , and spathic ores , forms of siderite. The rest of 
this case is occupied by ores from the western states. 
Case 16. — A series of limonites from the eastern states 
that illustrate the transition from a porous, impure bog-iron ore, 
to a compact brown limonite and through gothite and turgite to 
hematite. 
Case L. — -Iron ores, Virginia. These are arranged in the 
order of their ages— from the archaean magnetites of the Blue 
Ridge to the siderite concretions of the coal measures. 
