Prized for Millennia, Nephrite Jade Is the World’s Toughest Natural Mineral

In the world of gemstones, hard and tough are two very different things. While diamond may be the hardest material known to man, when rating a gemstone’s resistance to breaking or chipping, a special variety of jade rises to the top of the “toughest minerals” list.

For millennia, nephrite jade has been revered not only for its beauty, but also for its incredible toughness. Ancient civilizations prized this resilient stone, shaping it into weapons, tools, sacred artifacts — and jewelry.

The Chinese, as early as the Neolithic period (3500–2000 BC), crafted nephrite into ritual blades and ceremonial vessels, believing it symbolized strength and immortality. The Māori of New Zealand used it for chopping tools and war clubs, passing them down through generations. Even today, in China, a pierced jade disk is a symbol of heaven.

Unlike other stones that shatter under pressure, nephrite’s densely interwoven fibrous structure makes it nearly unbreakable — perfect for practical, spiritual and decorative uses.

Interestingly, super-resilient nephrite jade scores a modest 6 to 6.5 on the Mohs hardness scale. Diamond, by comparison, rates a perfect 10.

And the gap in hardness is even more amplified by the fact that the Mohs scale is not linear. For example, diamond at “10” is four times as hard as corundum at “9”, and corundum is twice as hard as topaz at “8”.

The relative softness of nephrite makes it easy to fabricate into rings, necklaces, pendants, anklets and beaded bracelets.

According to the Gemological Institute of America, for both nephrite and its pretty cousin, jadeite, green is the most valued color. Semi-transparent clarity and fine texture also increase jade’s value dramatically. The most common colors of nephrite jade are shades of green (from pale to “spinach”), but they also occur in white, gray and black.

While jadeite has a slightly higher hardness rating than nephrite, the fibrous crystal structure of the latter makes it significantly tougher.

Nephrite jade is mined in Canada, China, Australia, Russia, Taiwan and the US, specifically in the states of Wyoming, Wisconsin and Washington.

Credit: Jewelry photo by Lê Phạm Gia Hy, CC BY-SA 4.0, via Wikimedia Commons. Close-up photo by James St. John, CC BY 2.0, via Wikimedia Commons.