HISTORY, NAME, LOCALITIES: Kyanite, collected since antiquity for its long, blue crystals, was recognized as a mineral species in 1789. Its name stems from the Greek kyanos, meaning “blue,” alluding to its typical blue color. Kyanite is an abundant mineral that occurs worldwide. Notable collecting localities are located in Brazil, Italy, Austria, Switzerland, Namibia, China, Australia, and the United States (Georgia, Virginia, North Carolina, New Hampshire, Vermont, South Dakota.)
MINERALOGY, PROPERTIES, OCCURRENCE: Kyanite [aluminum silicate, Al2SiO5], pronounced KYE-an-ite, crystallizes in the triclinic system, usually as elongated, tabular or bladed, prismatic crystals that are translucent to transparent, rarely terminated, and frequently twinned. It has a Mohs hardness of 4.5-5.0, perfect cleavage in one direction, vitreous luster, a specific gravity of 3.5-3.6, and a color that is primarily blue but varies with impurities. Kyanite occurs primarily in aluminous rocks that have been altered by high-pressure, regional metamorphism.
METAPHYSICAL PROPERTIES, LORE, USES: Medieval physicians prescribed powdered kyanite to alleviate sinus problems and muscular pain. Modern metaphysical practitioners use kyanite to enhance creativity, broaden perspectives, and promote mutual understanding. It is thought to be a stone of attunement that brings the calmness and tranquility necessary for meditation. Transparent, flawless kyanite is a minor gemstone that is faceted into gems; translucent kyanite is fashioned into cabochons and beads. Kyanite is mined extensively and used to manufacture refractory and ceramic materials.
COLLECTORS’ INFORMATION: Kyanite is collected for its pleasing blue color and long, bladed crystals as both individual and composite specimens, the latter in association with staurolite, quartz, and muscovite.
QUARTZ (var. ROCK CRYSTAL)
HISTORY, NAME, LOCALITIES: Rock crystal, which is common and occurs worldwide, has been collected since prehistory. Notable collecting localities are found in India, Brazil, Germany, Peru, Bolivia, Namibia, Russia, and the United States (Arkansas, Colorado, Maine, Connecticut, Virginia).
MINERALOGY, PROPERTIES, OCCURRENCE: Rock crystal is the transparent, colorless variety of macrocrystalline quartz [silicon dioxide, SiO2). The word “quartz” is believed to have originated with the Slavic kwardy, meaning “hard,” in allusion to its substantial hardness. It crystallizes in the hexagonal system and occurs mainly in hydrothermal veins, granite pegmatites, and as geode linings as short-to-long, horizontally striated, hexagonal, prismatic crystals with pyramidal terminations and distinctive, water-clear transparency. It has a Mohs hardness of 7.0, a conchoidal fracture, vitreous luster, and specific gravity of 2.65.
METAPHYSICAL PROPERTIES, LORE, USES: Rock crystal has since antiquity been one of the most widely collected of all minerals. It has served as a gemstone and ornamental stone in many cultures. Until quartz was synthesized in the 1960s, rock crystal was vital to electronic frequency controls, filters, and timing devices. Modern metaphysical practitioners call rock crystal the “universal crystal” because of its numerous abilities to sharpen insight, enhance spiritual development, improve concentration, refine focus, and energize the mind.
COLLECTORS’ INFORMATION: Rock crystal is widely collected for its brilliant transparency, superb hexagonal crystal development, and frequent occurrence on large plates and in geodes to make interesting display pieces.