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 Post subject: SHORT NOTES ON NIGERIAN AMETHYST, THE UNKNOWN VIOLETS
PostPosted: Thu Feb 16, 2017 6:09 pm 
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Joined: Tue Jun 28, 2016 3:08 pm
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Location: Jos, Nigeria
SHORT NOTES ON NIGERIAN AMETHYST, THE UNKNOWN VIOLETS

It’s a fact; some of the finest cuts in the gems trade are made from amethyst rough. Strangely cheap with exciting tones ranging from pale lilac through to deep reddish purple. Presently, supply from Africa is dominated by the Zambians, with a reputation for brilliant and peerless deep shades of violet. This domination being an anomaly considering many African countries have considerable quantities of untapped amethyst reserves in metamorphic igneous rock zones which should produce stones of equal brilliance(even if not the bespoke purple hues from Zambia) given some professional sorting is applied.
Personally I’d attribute this anomaly to low prices and profit margins obtainable from working amethyst by miners outside the fame zones of Zambia and possibly Morocco, (my opinion only though). Various color variations and secondary colors are to be found in Nigerian Amethyst, given the vast metamorphic belt within the country – in itself almost the entire size of Zambia, with material usually ranging from Non facet-grade collections brilliant colored material of significant sizes and excellent clarity. Recently though, amethyst of interesting character (mainly deep purples stones with zero secondary colours nor inclusions and excellent clarity) have been appearing frequently, and is regularly picked up by Asians who scour gem-trade centers endlessly, originally attracted by cheap colorless Topaz(usually supplied by the ton), or the big-three Nigerian Exotics(Sapphire, Tourmaline and Aquamarine).
Source Locations in Nigeria
Across the vast metamorphic-complex of Nigeria Amethyst can be found in significant quantities with gem grade material especially concentrated around in Ba’de(Kaduna State), Toro and Ningi(Bauchi State),
Faceting Potential
Various parcels of Nigerian Amethyst seen by the author including the popular deep purple type indicated in the pictures below show no color zoning at all. Clarity of these parcels ranges from VS-VVS, with certain parcels having up to 75% of contents in the VVS category. Sizes range from 5-100cts for brilliantly coloured stones while certain stones with light purple hues have been found in sizes up to 500cts.
Prices for the best stones range from 0.5USD-10USD/cts for the best stones (deep purple+VVS/VS), while lower grades are priced less though prices can vary sharply based on seasonality. Although local faceting culture is limited, certain cutters are already taking advantage of the availability of these stones at local prices.
While sales have been heating up recently with a few finds yielding spectacular stones (Toro-Bauchi especially), no extensive analysis have been undertaken for this development. Research on these stones will most likely depend on sustainability of mines found recently.


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