Corundum Beads
Corundum beads are crystalline aluminum oxide, the mineral behind both ruby and sapphire and, at 9 on the Mohs scale, the hardest common gemstone after diamond. This collection holds every corundum we stock: ruby, blue and yellow sapphire, mixed ruby and sapphire strands, and the rocks that carry ruby crystals, ruby zoisite, ruby kyanite, ruby fuchsite and ruby in hornblende, in a range of finishes and shapes for bracelets, necklaces and earrings.
Appearance
Ruby is red corundum, colored by chromium; everything else is sapphire. Beads are cut from included, translucent to opaque crystal rather than fine gem rough, so ruby beads run from pink-red to a deep raspberry with a slightly cloudy look, and blue sapphire beads range from grey-blue to inky navy, often with lighter and darker beads on one strand. Yellow sapphire gets its color from iron.
The ruby rocks look different. Ruby zoisite from Tanzania is green zoisite with red ruby and black hornblende; ruby kyanite sets red ruby in blue kyanite; ruby fuchsite is ruby in a pale green mica; ruby in hornblende is red on black. Faceting suits the pure corundum; the matrix stones are usually polished smooth to show the pattern.
Formation and origin
Corundum forms where aluminum-rich rock is heated and compressed with too little silica to make feldspar or clay, mostly in marble and metamorphosed basalt, and also in some igneous rocks. Chromium gives ruby its red; iron and titanium together give sapphire its blue. Sources include Sri Lanka, Myanmar, Thailand, Madagascar, Tanzania, Mozambique and India, and the ruby-bearing rocks come mainly from Tanzania and southern India. Spinel and garnet are the historic look-alikes for ruby.
Pairings
Clear quartz beads: colorless spacers let the ruby reds and sapphire blues read clearly without adding a competing color.
Black onyx beads: a glossy black ground that makes deep ruby and navy sapphire look richer.
Hematite beads: gunmetal grey spacers match the dark, inky tone of bead sapphire and take the wear easily.
Meaning and Metaphysical Beliefs
Corundum has long been regarded as royal. Ruby was called the king of gems in ancient India, where it was associated with power and passion, and sapphire was worn by clergy in medieval Europe as a symbol of heaven and wisdom. In modern crystal traditions ruby is linked with the root and heart chakras and sapphire with the throat and third eye. These are traditional beliefs, not claims of physical effect.
