This sample of trapiche is displayed in the Smithsonian Museum of Natural History. Trapiche is a variety of beryl, and is often referred to as trapiche emerald since it has a green color. It is a silicate mineral of beryllium and aluminum. It has the composition Be3Al2Si6O18. These gem samples are 5.3 and 4.9 carats and are from Colombia.
The name trapiche is the spanish name for a machine with large wooden spokes, used for crushing juice out of sugar cane.