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Multicoloured Bismuth-bearing Tourmaline from Lundazi, Zambia

Mary L. Johnson, Cheryl Y. Wentzell, September 1, 1997

Tourmalines from an alluvial deposit near Lundazi in Zambia consist of colour-zoned pink/colourless/yellow-green “watermelon” nodules.

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15 ct tanzanite
Pleochroism in Faceted Gems: An Introduction

Richard W. Hughes, October 31, 2014

Describes the phenomenon of pleochroism and its complex effect on the appearance of coloured stones.

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The internal structures of natural pearls from the marine mollusk Pinctada maxima are the subject of the lead article in this issue. The scattered loose pearls on the cover are from Paspaley’s natural pearl collection, which includes one discovered in the 1970s at the Eighty Mile Beach fishing grounds
G&G Spring 2021 Edition
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