BLACK JADE NEPHRITE SLAB A-GRADE 67
Lovely slab of rough genuine Black Jade Nephrite Slab A-Grade 67. Polishes to a very high luster, which is perfect for creating stunning quality Black Jade mirror finish jewellery and pendants. One photo taken dry, one wet. This material will polish to a stunning black luster. Nephrite Jade is the toughest of all naturally occurring materials. Nephrite Jade has been used from ancient times as jewellery, tools and weapons. Check this Mirror Finish Showing also how Black this mineral is.
Cowell, South Australia.
7.2cm x 6.8cm x 0.8cm, 106g.
Nephrite is a rock comprising mostly massive microcrystalline to cryptocrystalline felted amphiboles of the tremolite actinolite series. Nephrite is one of the two rocks termed as jade, the other being Jadeitite or jadeite jade, consisting mostly of jadeite. Both are extremely tough and resistant to fracture such that they have been used for making choppers and blades since Neolithic times. In addition to amphibole, nephrite can contain minor to trace amounts of the following:
Diopside, grossularitic garnet, magnetite, chromite, graphite, apatite, rutile, pyrite, datolite, vesuvianite, prehnite, talc, the serpentine polymorphs and titanite.
Nephrite is actually not a mineral, but a variety of the mineral actinolite. The nephrite variety is composed of fibrous crystals inter-twinned in a tough compact mass. Other actinolite varieties are quite different from nephrite. The toughness of jade is remarkable. It has a strength greater than steel and was put to work by many early civilizations for axes, knives and lethal weapons. It was later that jade became a symbolic stone used in ornaments and other religious artifacts.
Black Nephrite Jade is caused by an inclusion of more than 7% Iron. It is possible to obtain the highest polish of any other stone and the toughest stone in the world. We think this is one of Australia’s most under appreciated gemstones considering the material from Cowell is some of the best black Jades in the world.