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Huge Leuco Garnet - Possible Record Breaker

Posted by Paul Stahl  
avatar Huge Leuco Garnet - Possible Record Breaker
December 19, 2011 05:45AM
Hi Everyone,

We recently obtained some stones from a Maasai friend in Northern Tanzania who had been keeping them since the 1970s. Amongst the stones were some some large pale Grossular Garnets that came out of the Umba River. They range from pale lemon yellows to pure white Leucos. Here is the pick of the bunch - a Leuco Garnet that weighs in at 87.62CTs. It is very clean and will easily finish a VVS stone. It is 30mm Long 20mm Wide and 17mm in Depth. We have shown it to Gemmologists and Valuers who have no idea what it may possibly be worth as there are no known stones of similar size and clarity. Many have stated that they believe it may be the largest recorded high-facet grade Leuco Grossular Garnet ever found.

Any input would be appreciated.



Edited 2 time(s). Last edit at 12/19/2011 04:07PM by Paul Stahl.
open | download - 87.62CT Leuco Grossular Garnet A.jpg (194.3 KB)
open | download - 87.62CT Leuco Grossular Garnet.jpg (205.2 KB)
avatar Re: Huge Leuco Garnet - Possible Record Breaker
December 19, 2011 10:08AM
Interesting, but to avoid confusion you shouldn't use the term Leucite - which is a different mineral altogether.

avatar Re: Huge Leuco Garnet - Possible Record Breaker
December 25, 2011 06:04AM
These stones are quite valuable I would imagine depending on the degree of internal transparency and freedom from internal flaws. I would not want to speculate on their value without at least being able to examine them with a good light and probably in a high refractive index oil. If you can estimate the size of the stones that can be cut from them, look on the internet for price per caret of stones of comparable color and transparency and do the math.

Rock Currier
Crystals not pistols.
Re: Huge Leuco Garnet - Possible Record Breaker
December 25, 2011 12:39PM
Hard to see fine internal flaws without a polished window. These could affect the valuation significantly.

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