ore, metal-bearing mineral mass that can be profitably mined. Nearly all rock deposits contain some metallic minerals, but in many cases the concentration of metal is too low to justify mining mining, extraction of solid mineral resources from the earth. These resources include ores, which contain commercially valuable amounts of metals, such as iron and aluminum; precious stones, such as diamonds; building stones, such as granite; and solid fuels, such as
..... Click the link for more information. the ore. Ores are usually found concentrated in deposits with a definite gradation of metal concentration from the ore to the surrounding rock. The ore often occurs in veins, which are ore-filled fissures in the rock. The veins vary in thickness from only fractions of an inch to several hundred feet. Minerals with no commercial value, called gangue minerals, are usually found mixed with the ore in the vein. Some veins are buried deep within the ground, but others lie close to the surface. Veins of ore exposed to weathering are often eroded and redeposited in placers and alluvial deposits, e.g., ore-bearing stream and lake gravels or beach sands. Some ores are simple chemical compounds, while others are chemically complex minerals mineral, inorganic substance occurring in nature, having a characteristic and homogeneous chemical composition, definite physical properties, and, usually, a definite crystalline form. A few of the minerals (e.g.
..... Click the link for more information. . Important ores of aluminum aluminum (əl
..... Click the link for more information. , iron iron, metallic chemical element; symbol Fe [Lat. ferrum]; at. no. 26; at. wt. 55.847; m.p. about 1,535°C;; b.p. about 2,750°C;; sp. gr. 7.87 at 20°C;; valence +2, +3, +4, or +6. Iron is biologically significant.
..... Click the link for more information. , manganese manganese (măng`gənēs, măn`–) [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.938; m.p.
..... Click the link for more information. , and tin tin, metallic chemical element; symbol Sn [Lat. stannum]; at. no. 50; at. wt. 118.69; m.p. 231.9681°C;; b.p. 2,270°C;; sp. gr. 5.75 (gray), 7.3 (white); valence +2 or +4. Tin exhibits allotropy ; above 13.
..... Click the link for more information. are oxides; important ores of antimony antimony (ăn`tĭmō'nē) [Lat. antimoneum], semimetallic chemical element; symbol Sb [Lat. stibium,=a mark]; at.
..... Click the link for more information. , copper copper, metallic chemical element; symbol Cu [Lat. cuprum=copper]; at. no. 29; at. wt. 63.546; m.p. 1,083.4°C;; b.p. 2,567°C;; sp. gr. 8.96 at 20°C;; valence +1 or +2. Copper and some of its alloys have been used by humanity since the Bronze Age .
..... Click the link for more information. , lead lead, metallic chemical element; symbol Pb [Lat. plumbum]; at. no. 82; at. wt. 207.2; m.p. 327.502°C;; b.p. about 1,740°C;; sp. gr. 11.35 at 20°C;; valence +2 or +4.
..... Click the link for more information. , mercury mercury or quicksilver [from the Roman god Mercury], metallic chemical element; symbol Hg [Lat. hydrargyrum=liquid silver]; at. no. 80; at. wt. 200.59; m.p. −38.842°C;; b.p. 356.58°C;; sp. gr. 13.
..... Click the link for more information. , nickel nickel, metallic chemical element; symbol Ni; at. no. 28; at. wt. 58.69; m.p. about 1,453°C;; b.p. about 2,732°C;; sp. gr. 8.902 at 25°C;; valence 0, +1, +2, +3, or +4.
..... Click the link for more information. , silver silver, metallic chemical element; symbol Ag [Lat. argentum]; at. no. 47; at. wt. 107.8682; m.p. 961.93°C;; b.p. 2,212°C;; sp. gr. 10.5 at 20°C;; valence +1 or +2.
..... Click the link for more information. , and zinc zinc, metallic chemical element; symbol Zn; at. no. 30; at. wt. 65.38; m.p. 419.58°C;; b.p. 907°C;; sp. gr. 7.133 at 25°C;; valence +2. Zinc is a lustrous bluish-white metal. It is found in Group 12 of the periodic table .
..... Click the link for more information. are sulfides. Some metals, called native metals, occur uncombined in nature, e.g., copper, gold gold, metallic chemical element; symbol Au [Lat. aurum=shining dawn]; at. no. 79; at. wt. 196.9665; m.p. 1,064.43°C;; b.p. 2,808°C;; sp. gr. 19.32 at 20°C;; valence +1 or +3.
..... Click the link for more information. , platinum platinum (plăt`ənəm), metallic chemical element; symbol Pt; at. no. 78; at. wt. 195.08; m.p. 1,772°C;; b.p.
..... Click the link for more information. , and silver. The recovery of metals from their ores is one area of the field of metallurgy metallurgy (mĕt`əlûr'jē), science and technology of metals and their alloys .
..... Click the link for more information. .

ore

Aggregate of economically important minerals that is sufficiently rich to separate for a profit. Although more than 3,500 mineral species are known, only about 100 are considered ore minerals. The term originally applied only to metallic minerals (see native element) but now includes such nonmetallic substances as sulfur, calcium fluoride (fluorite), and barium sulfate (barite). Ore is always mixed with unwanted rocks and minerals, known collectively as gangue. The ore and the gangue are mined together and then separated. The desired element is then extracted from the ore. The metal may be still further refined (purified) or alloyed with other metals.

ore (redirected from Mineral ores)

ore

ore
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