Chrysoprase is the most valuable of the chalcedonies, a luminous apple-green stone coloured by traces of nickel. Its fresh colour can look remarkably like fine jade, which is why it has sometimes been nicknamed Australian jade. And Australia is indeed the key source, especially the Marlborough district in Queensland, with more material from Tanzania, Indonesia and Poland. It was a favourite of Frederick the Great of Prussia, who decorated buildings and jewellery with it in the 1700s.
At 6.5 to 7 on the Mohs scale with chalcedony's dependable toughness, chrysoprase handles daily wear happily. It is cut as cabochons and beads to show its even, glowing green. One care note: its colour comes partly from water in the stone, so long stretches of strong sunlight or heat can fade it, though rest in a damp cloth can sometimes revive it. Dyed green chalcedony is a common imitation, and it usually looks flatter and more artificial than the real thing, which is all we sell.
Green aventurine and variscite share its fresh green, and nephrite jade is its classic look-alike.
