Jewelry with Nephrite jade

The term "jade" is not clearly assigned to a mineral, but is used for various green gemstones, mostly made of Nephrite or Jadeite. The term was adopted from French around 1800 and in turn goes back to the Spanish term ijada for "soft, flank". In the compound piedra de la ...

The term "jade" is not clearly assigned to a mineral, but is used for various green gemstones, mostly made of Nephrite or Jadeite. The term was adopted from French around 1800 and in turn goes back to the Spanish term ijada for "soft, flank". In the compound piedra de la ijada, it means flank stone, loin stone, as the Spanish had already discovered that (Nephrite) jade was used by the indigenous people of Latin America as a protective stone for the kidneys, etc.

n Europe, a number of different minerals are incorrectly referred to as "jade". In the narrower sense, jade refers to gemstones that have a specific property: The constituents must be present in microcrystalline form, i.e. as matted fibers or grains that can only be seen with a microscope. This applies to Nephrite and Jadeite; both have a very high toughness and breaking strength due to the felting.

Nephrite is a matted aggregate of tiny fibers and needles, which usually consists of the mineral Actinolite. Jadeite, on the other hand, is a sodium aluminum silicate with a Mohs hardness of 6.5 - 7, which is about one degree of hardness higher than Nephrite. The coloring element in Nephrite is primarily iron. The higher the iron content compared to the magnesium content, the more intense the green coloration.