What Is Jade?
Jade refers to either of two durable, compact, typically green gemstones that take a high polish. Since records began, both minerals have been carved into jewellery, ornaments, small sculptures, and utilitarian objects. Today, jadeite is the most coveted jade stone; the other is nephrite.
This article provides a brief history of jade, distinguishes between the two jade stones, explains its composition and structure, and introduces three stunning pieces of jade jewellery.
Two types of jade: Jadeite and nephrite
When worked and polished, the two types of jade are distinguishable by their appearance. Polished nephrite, for instance, is oily rather than vitreous (glassy), while jadeite is the opposite. There are marked variations of translucency in both stones, too. What’s more, some colours are distinct to one stone or the other – for example, the immensely popular apple and emerald-green jades in jewellery are invariably jadeite.
Where is jade found?
In terms of geographical location, the northern Myanmar city, Mogaung, and its surrounding area has been the primary source for gem-quality jadeite for decades, while nephrite is more abundant and globally widespread.
A brief history of jade
Through the ages, jade has been cut and shaped with sandstone, slate, and quartz sand (as an abrasive) by tools made of bronze and iron before the dawn of the 19th century ushered in machine-powered lathes, steel saws, and diamond-pointed drills. Today, carborundum and diamond dust are used as abrasives in place of crushed garnets and corundum.
Both jade stones were worked into implements by Neolithic peoples in many parts of the world, with the best-known finds unearthed from the lake dwellings of Switzerland, France, Central America, China, and Mexico.
Jade is hard, heavy, and durable and maintains a good edge – Neolithic artisans coveted these physical properties coupled with its fine hues and warm polish. However, when the Neolithic cultures were succeeded by those using bronze and iron, jade gradually lost its industrial value and favour as a gemstone in all but a few regions.
Use of jade as a gemstone
Jade’s durability and dazzling colour spectrum make it highly desirable and a centrepiece of a glittering array of jewellery items, including pendants, necklaces, rings, bracelets, earrings, beads, cabochons, tumbled stones, and more. These items are often made of solid jade and combined with other gems or placed in settings made from gold, silver, or other precious metals.
Jadeite and nephrite: Composition and structure
Jadeite and nephrite differ in both chemical composition and crystalline structure. Jadeite is a silicate of sodium and aluminium and categorised as pyroxene (Px). In contrast, nephrite is a silicate of calcium and magnesium and classed as tremolite. Both stones’ internal crystals are tightly interlocked, forming a compact aggregate. Both jade stones may be white or colourless, but hues including red, green, and violet may occur due to the presence of iron, chromium, or manganese impurities.
Physical properties of jade
|Chemistry||Silicate – pyroxene.||Silicate – amphibole.|
|Colour||Usually various shades of white to dark green, sometimes grey, pink, lilac, red, blue, yellow, orange, black, coloured by impurities.||Usually ranges in colour between white, cream, and dark green.|
|Lustre||Vitreous to sugary.||Vitreous, greasy, silky, waxy.|
|Diaphaneity||Translucent to opaque. Rarely semi-transparent.||Translucent to opaque. Rarely semi-transparent.|
|Cleavage||Usually not seen because of small grain size and splintery fracture.||Prismatic but usually not seen because of small grain size and splintery fracture.|
|Mohs Scale Hardness||6.5 to 7||6 to 6.5|
|Specific Gravity||3.3 to 3.5||3.0 to 3.3|
|Diagnostic Properties||Refractive index, toughness, hardness, specific gravity, grain size and habit.||Colour, toughness, hardness, specific gravity, grain size, and habit.|
|Chemical Formula||NaAlSi2O6 or Na(Al,Fe3+)Si2O6||Ca2(Mg,Fe)5Si8O22(OH)2|
|Refractive Index||1.66 to 1.68
|1.60 to 1.63
|Uses||Jewellery, ornaments, tools, weapons, gemstones.||Jewellery, ornaments, tools, weapons, gemstones.|
Antique jade jewellery
Embrace nature with these exquisite jade leaf earrings; intricately carved and set within a custom-crafted yellow gold setting. The dazzling emerald-green hue is complemented by the earrings’ luminous yellow gold band, creating an elegant, high-contrast finish.
Featuring three vivid verdant jade leaves set at right angles, these delightful drop earrings are sure to make a statement. A small rubover set diamond centres the three jades and connects, via an articulated drop of six old cut diamonds, to a larger diamond linked to the fishhook backs.
This modern, Victorian-inspired ring features three glowing Australian jade stones, contrasting dramatically with the 18k yellow gold band. Four white brilliant-cut diamonds nestle between the stone, adding a touch of sparkle. The beautifully etched gallery continues in the shoulders, fashioning a modern classic faithful to its Victorian roots.