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| | Mineral (Site not responding. Last check: ) |
 | | Minerals are named in various ways, some in honour of a person (weloganite, after Sir William E.), a locality (athabascaite), an institution (mcgillite), the chemical composition (cobaltite), or a distinctive property such as colour (azurite) or shape (cylindrite). |
 | | Concentrations of minerals range from small occurrences to large deposits and are formed by various processes, including solidification of mineral-bearing solutions in rock openings (eg, fissures, cavities), precipitation from mineral-rich waters as in springs and saline lakes, and solidification of gases during volcanic eruptions. |
 | | Colour in minerals results from atoms or structural defects (colour centres) that absorb certain portions of the spectrum of light; the unabsorbed portion is reflected or transmitted to the eye as colour. |
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