Ores of Common Metals Collection

The term "ore" is used in connection with a rock or mineral mass when it contains enough of an element or compound to make it economically feasible to mine. 15 specimens of the more important ores are included. Approximately 1 1/2". A mineral or rock, which contains enough of a chemical element to make it economically feasible to mine, is called an ore.

Ores of Common Metals Collection

Ore is used in describing rocks containing a metallic element or elements, and may be used in connection with nonmetallic substances.

In nature the ore minerals are found in veins or in deposits in association with rocks of little or no value. In native ores the valuable element is found free as an element.

Gold, silver, platinum and copper may occur as elements.

More commonly the element to be recovered is chemically combined with sulfur, oxygen, carbon, silicon or other elements and must be separated from them.

The separation of the desired element is done by roasting, smelting, electrolysis or various chemical treatments.

Sources of Aluminum

1. BAUXITE - Product of leaching from aluminum bearing rocks in tropics.

(Other Sources: diaspore, gibbsite, boehmite, and cryolite)

Sources of Copper

2. CHALCOPYRITE - Occurs in hydrothermal veins and replacement deposits.
3. MALACHITE - Occurs in oxidized copper veins as a supergene mineral.

(Other Sources: native copper, chalcocite, bornite, cuprite, chrysocolla, azurite)

Sources of Iron

4. PYRITE - Pyrite is formed in both high and low temperature igneous & metamorphic rocks.
5. HEMATITE - Large deposits are formed by leaching or iron bearing rocks.
6. MAGNETITE - Occurs in large beds and lenses in metamorphic rocks.
7. LIMONITE -A weathered product of iron minerals.
8. PYRRHOTITE - Found in deposits associated with basic igneous rocks.
9. SIDERITE - Occurs in concentric layers in shale and clay formations.

(Other Sources: goethite)

Sources of Lead

10. GALENA - Found in hydrothermal veins.

(Other Sources: cerussite, anglesite, vanadinite, and wulfenite)

Sources of Magnesium

11. DOLOMITE - Replacement mineral after limestone in sedimentary strata.

(Other Sources: magnesite, carnallite, and brucite)

Sources of Manganese

12. PYROLUSITE - Develops in deposits from sea floors and lake bottoms.

(Other Sources: manganite, franklinite, rhodochrosite, and rhodonite)

Sources of Tin

13. CASSITERITE - Found near granitic rocks in hydrothermal veins.

Sources of Zinc

14. SPHALERITE - Occurs in replacement deposits and hydrothermal veins.

(Other Sources: smithsonite, hemimorphite, franklinite, and willemite)

Alloys

15. BERYL - Found in granitic rocks and pegmatites.

(Other Examples: molybdenite)