Ruby- Corundum Mineral Specimen
CORUNDUM (var. RUBY)
HISTORY, NAME, LOCALITIES: The ruby variety of corundum has been collected since antiquity. The name “corundum” stems from kuruvinda, the ancient Sanskrit word for “ruby”; the word “ruby” derives from the Latin rubbeus, meaning “reddish.” Ruby is collected in Myanmar, Tanzania, Sri Lanka, Thailand, Russia, Malawi, and the United States (North Carolina).
MINERALOGY, PROPERTIES, OCCURRENCE: Corundum [aluminum oxide, Al2O3], pronounced coh-RUN-dum, crystallizes in the hexagonal system as tapering prismatic or pyramidal crystals in rough and rounded barrel shapes and as granular masses. It has Mohs hardness of 9.0, no cleavage, and a specific gravity of 3.9-4.1. Corundum is transparent to translucent and can occur in all colors. The transparent, red gem variety is ruby; all other colors are sapphire. The red color of ruby is due to the presence of trivalent chromium ions. Corundum occurs in nepheline syenite pegmatites, metamorphic rocks, and secondary alluvial deposits.
METAPHYSICAL PROPERTIES, LORE, USES: Ruby was one of the first precious gemstones ever mined and is the birthstone for July. Modern metaphysical practitioners believe that ruby inspires love and spirituality, enhances creativity and wisdom, imparts confidence and courage, and stimulates leadership abilities. Natural non-gem-quality ruby crystals were once fashioned into jewel bearings for fine watch movements. Transparent ruby, one of the classic precious gemstones, is faceted into very costly gems; translucent ruby is fashioned into cabochons.
COLLECTORS’ INFORMATION: Ruby specimens are collected for their rarity, color, and crystal habits.B