Jade

Nephrite has a hardness of 6-6.5 on the Mohs scale, while Jadeite is 6.5-7. Its color ranges from white to dark green, often with mottled or banded patterns. It typically has a greasy to vitreous luster. Nephrite forms in a fine, compact, intergrown fibrous habit, making it exceptionally tough. Jadeite has a granular to fibrous texture. Both have no distinct cleavage.

Nephrite is a metamorphic rock formed from the alteration of magnesium-rich rocks (like serpentinite) under high pressure and relatively low temperatures. Jadeite is also metamorphic, forming in subduction zones under conditions of high pressure and relatively low temperature. The geological age varies greatly depending on the specific deposit.

Jade has been prized for centuries in many cultures for carvings, sculptures, jewelry, and ornamental objects due to its beauty and exceptional toughness. It's popular for cabochons, beads, and polished spheres (like those pictured).

Jade has a rich cultural history, particularly in ancient China, Mesoamerica, and New Zealand (Maori culture). The term 'jade' itself refers to either of the two distinct minerals (Nephrite or Jadeite) and distinguishing between them can require laboratory analysis. Its toughness, not hardness, is what makes it so resistant to breaking.

In the field, raw jade can be difficult to identify without experience, as it often occurs within serpentinite or other metamorphic rocks. Look for its characteristic waxy luster and tough, compact texture. The color can be a good indicator, but other green minerals exist. To confirm, one might perform a scratch test (though not advised on a polished specimen) or, for definitive identification, specific gravity or refractive index measurements are used. Major deposits are found in places like China, Myanmar (Burma), Russia, Canada, New Zealand, and the United States (Wyoming, California).