Guest Author - Susan Dorling

One of my favorite gemstones is jasper. I collect rings, especially ‘big’ rings, and recently bought a knuckle duster of a picture jasper set into a primitive and wonderful handmade setting of sterling silver. I am drawn to this ring like a moth to a flame. Next to some of my turquoise doozies, this big brown and cream cafe au lait beauty with the intricate Picasso-like abstract pattern is my favorite acquisition so far this year. And ever since I have been putting jewelry together for my own company, Silver Spirit Designs, I consistently choose jasper here and there or exclusively stand alone to add warmth and richness to my designs. It’s interesting to note that jasper falls in and out of fashion, but it will surely always be one of my favorites!

Jasper is an opaque, solid or patterned variety of cryptocrystalline quartz (or ‘chalcedony’ which includes carnelian, sard, plasma, prase, bloodstone, onyx, sardonyx, chrysoprase, thundereggs, agate, flint, chert, jasper, petrified wood, and petrified dinosaur bone just to name a few of the better known varieties). This material consists of tiny quartz crystals colored by various mineral impurities. The names of various jaspers comes from their color: bloodstone, green, lemon— from their pattern: orbicular, poppy, leopardskin, landscape, Picasso—or from a place name: Morrisonite, Mookaite. All types take an excellent polish, are trouble free to care for, and hardy enough for all jewelry uses. Stones are usually cabbed (as in cabochons), sometimes carved, and rarely faceted.

Jewelry use of jaspers goes back to the early history of civilization and has been in and out of fashion many times. For some years now opaque gemstones have been in fashion so jaspers are widely used by contemporary jewelry designers. Jaspers are found all over the world, with certain colors or patterns unique to particular locales. For example, most bloodstone comes from India, Mookaite comes exclusively from Australia.

History of Jasper
With the exception of animal bones, sticks, plain rocks, and possibly Obsidian, chalcedony was the earliest raw material used by humankind and chosen for its abundance, durability, and beauty. Early man made projectile points, knives, tools, and containers such as cups and bowls, and jewelry. For someone who loves history and gemology equally, this knowledge of jasper’s origin lends the gemstone a particularly exciting edge that comes alive in bracelets, necklaces, and earrings, and works wonders in jewelry design.

Value of Jasper
Most jaspers are common and much of the value in a piece relates to the saturation of its color, the beauty of its pattern, or the artistry with which it is fashioned. Some types such as Imperial Jasper and Madagascar Jasper do command premium prices for their relative rarity.


Gemological Data of Jasper
Makeup: Silicon Dioxide
Crystal Structure: Trigonal
Hardness: 7
Luster: Vitreous
Density: 2.61
RI: 1.53-1.54
DR: 0.004
Cleavage: none

Article Reference: Barbara W. Smigel, Graduate Gemologist, GIA, Artistic Colored Stones