Jeffrey Bergman has been collecting trapiche sapphires for over a decade and has assembled the largest collection known, rivaling the quality of pieces in the finest museum collections.
While the vast majority of trapiche sapphires are either opaque blackish blue with gray spokes or translucent dark gray on light gray, very occasionally, he would acquire a translucent gemmy vivid blue on snow white trapiche sapphire.
The collection on display at the Gem & Jewelry Exchange (GJX) in Tucson this year was made up of is comprised of several dozen of the typical opaque or gray type trapiche sapphires…but then there were three of gem quality; a 3.90ct and an 8.70 carat gem with GIA reports, and an extraordinary 36.16 carat gem with GRS and Gubelin lab reports.
The Gubelin lab report and appendix:
“The Spanish word trapiche, cogwheel in English, designates the agricultural tool which in former days was used to crush sugarcane. In the world of gems the same term is used for gemstones which show a characteristic six-rayed star pattern in cross-section.
 For a long time this peculiar appearance was only known from emerald, and is due to bands of dark inclusions which radiate from the center of the crystal – the optic axis – to the crystal faces. Only in the past twenty years other trapiche gemstones have been discovered, namely trapiche ruby, trapiche tourmaline, and trapiche sapphire.
For a long time this peculiar appearance was only known from emerald, and is due to bands of dark inclusions which radiate from the center of the crystal – the optic axis – to the crystal faces. Only in the past twenty years other trapiche gemstones have been discovered, namely trapiche ruby, trapiche tourmaline, and trapiche sapphire. This 36.16 natural sapphire described in the above mentioned Gubelin Gem Lab Report displays a distinct and well centered star. In addition, this remarkable gemstone has been spared thermal treatment. Such a combination of characteristics is very rare in Burmese sapphires of this size.”
Find the article at:
http://www.agta.org/pressroom/newsletters/prismnl2013volume3/index.html#/24/





 
				
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amazing collection indeed,very nice.