Trapiche emeralds consist of emerald crystals which contain inclusions of a mixture of albite feldspar and beryl. These inclusions radiate out from a hexagonal core to form a six spoke pattern.
Trapiche emeralds are unique to the Colombian deposits, but similar crystals have been found in Brazil and elsewhere. Trapiche is the Spanish word for cog wheels once used to crush sugarcane. If certain types of trapiche emeralds are cut as cabochons with the base perpendicular to the crystallographic axis of the crystal, a hexagonal chatoyancy may be seen. It is due to fibrous inclusions contained in each of the six spokes that radiate outward from the core.
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