軟玉

Nephrite is one of the two minerals that can be called true jade (the other being jadeite). It is a compact, fine-grained mass of interlocking amphibole fibres (tremolite to actinolite), and that felted structure makes it extraordinarily tough — historically used for tools and weapons as well as carvings.

Identifying nephrite

Nephrite ranges from creamy white ('mutton-fat' jade) through every shade of green to brown and black, with a smooth, slightly greasy lustre when polished. It is moderately hard (6–6.5) but, above all, exceptionally tough and resistant to breaking.

Where it is found

Nephrite has been treasured in China for millennia, with the classic source at Hetian (Khotan) in Xinjiang. It also occurs in Russia (Siberia), Canada (British Columbia), New Zealand (Maori pounamu) and elsewhere.