Gemstones are minerals that can be polished or cut for use as an ornament or jewelry. The color of a gemstone comes from the presence of trace amounts of transition metals. Take a look at the colors of common gemstones and the metals responsible for their color.
The name for amethyst derives from the Greek and Roman belief that the stone helped protect against drunkeness. Vessels for alcoholic beverages were made from the gemstone. The word is from the Greek a- (“not”) and methustos (“to intoxicate”).
Aquamarine gets its name for the Latin phrase aqua marinā, meaning “water of the sea”. This pale blue gemstone-quality beryl (Be3Al2(SiO3)6) exhibits a hexagonal crystal system.
Emerald is another form of beryl, this time in a green color due to the presence of both iron and titanium.
Garnet gets its deep red color from iron.
Corundum is any color besides red is called sapphire. Blue sapphires are colored by iron and titanium.
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