Green Garnet jewellery.
By Aamir Mannan. GREEN GROSSULAR GARNET
Transparent green gossular garnet has been found in Pakistan and in Tanzania and forms an attractive gemstone, though not approaching its illustrious cousin demantoid either in colour or dispersive power. the absorption spectrum shows little distinction in the specimens seen. The massive translucent green grosular found in transvaal and recently in Pakistan is more correctly called HYDROGROSSULAR as some of the
silica is replaced by water molecules. This can grade into californite, the massive green form of idocrase, which also contains hydroxyl ions. When hydregrossular is coloured green
by chromium, a broad band is seen in the orange, centered at 6300 A and with a notice ably sharp cut-off on the long-wave side. Californite. on the other hand, shows a strong band in the blue at 46I0 A (due to iron) and a weaker band in the green at 5300 A.
By Aamir Mannan. GREEN GROSSULAR GARNET
Transparent green gossular garnet has been found in Pakistan and in Tanzania and forms an attractive gemstone, though not approaching its illustrious cousin demantoid either in colour or dispersive power. the absorption spectrum shows little distinction in the specimens seen. The massive translucent green grosular found in transvaal and recently in Pakistan is more correctly called HYDROGROSSULAR as some of the 
silica is replaced by water molecules. This can grade into californite, the massive green form of idocrase, which also contains hydroxyl ions. When hydregrossular is coloured green
by chromium, a broad band is seen in the orange, centered at 6300 A and with a notice ably sharp cut-off on the long-wave side. Californite. on the other hand, shows a strong band in the blue at 46I0 A (due to iron) and a weaker band in the green at 5300 A. 
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