Colombian trapiche emeralds were first described by the French mineralogist Emile Bertrand (1879), in a meeting at the Société Géologique de France, in which he presented “curious crystals of emerald…from Muso, New Granada” though with no explanation on their formation and prior to them being named (Pignatelli et al.2015). Trapiche de caña de azucar is the Spanish name for the six-spoked cogwheel used to squeeze juice from sugarcane, so adopting the name “Trapiche” for emeralds exhibiting the same pattern is not only logical, but seems quite appropriate as well.

Visually, there are two major groups of trapiche emeralds; occasionally seen are those with beige colored albite radiating spokes separating the emerald sectors, and predominantly those with black carbon rich shale spokes. All trapiche emeralds were originally reportedly from Muzo on the western border of the Cordillera Basin, and erroneously from Chivor on the eastern border. It was later revealed that, in fact, Peña Blanca, also on the western border of the basin, was the actual source of the “Chivor” trapiches (Skalwold 2015). Trapiche emeralds have been found at Coscuez, also on the western border, but have never been described by geologists. Trapiche emeralds have not been found in Chivor, Gachala or Macanal on the eastern side (Pignatelli et al. 2015).
Gems & Gemology Fall 2015 feature article Colombian Trapiche Emeralds: Recent Advances in Understanding Their Formation provides an in-depth explanation for the formation of these fascinating gemological curiosities including a 3-D petrographic examination of their crystals with complete historical, geological, mineralogical, gemological, and crystallographic background. Two examples of non-Colombian trapiche emerald crystals have also been reported, one from the Brazilian state of Goiás and the other from the Mananjary area in Madagascar but they cannot be compared with Colombian samples because their geological formation is unknown (Pignatelli et al 2015).
“A-type” or “standard” trapiches feature dendritic spokes radiating from either a single point at the center, or from an emerald crystal core. A fascinating newer type first noted in 2009 from the Peña Blanca mine are “b-type” or “reverse” trapiches where emerald forms the six arms of the radiating star-like pattern rather than the beige albite or black shale (http://www.mindat.org/XKN-7D7 –Accessed 05 April 2016). And while the vast majority of trapiche emeralds are clarity enhanced by traditional methods, there are occasional very rare examples such as a 6.97-carat extremely rare “reverse” trapiche in the Somewhere In The Rainbow Collection verified as unenhanced by the AIGS lab under the directorship of Dr. Dietmar Schwarz (Fig.9).
“Emerald aficionados sooner or later find themselves seeking a well-formed trapiche for their collection. Once having acquired such a piece, in moments of repose and wonder, the gem gets pulled out of its paper and scrutinized; the color and texture of the very slightly bluish-green cabochon fills and satisfies the senses while the mathematical perfection of the six rays and the central hexagon alert the intellect to appreciate Nature’s design.

Of all the sciences, gemology lends itself to involve much more than just the usual analytic, de- constructive and intellectual phases with which science concerns itself. While science avoids subjectivity and aesthetics, gemology’s object of study, the gem, is nothing less than a thing of beauty, allure, timelessness, rarity, uniqueness, wholeness, perfection of color, and fineness: all immeasurables beyond the realm of science. Many of the world’s best gemologists know this to be true and some of them are able to use that to their advantage.” – author and emerald expert Ron Ringsrud (2016) The first known use of trapiche emerald in jewelry is in an early 19th century gold ring by an unknown artist bequeathed to the V&A museum in London by cleric and poet Reverend Chauncy Hare Townshend (V&A Search the Collections http:// collections.vam.ac.uk/item/O122705/ring-unknown/ –Accessed 05 April 2016). Trapiche emeralds have been featured in fine jewelry from prestigious names such as Bergdorf Goodman, Omi Prive, Spectrum Awards winner Erica Courtney and French joallier Francis Barth (Fig.12). A 172.5-carat Muzo trapiche parure from the collection of Victor Carranza sold for US$140,500 at Heritage Auctions, New York, in May 2012 (Fig.11).