Faceted Gemstones

Gems that are transparent are normally faceted, a method that shows the optical properties of the stone’s interior to its best advantage by maximizing reflected light which is perceived by the viewer as sparkle. There are many commonly used shapes for faceted stones. The facets must be cut at the proper angles, which varies depending on the optical properties of the gem. If the angles are too steep or too shallow, the light will pass through and not be reflected back toward the viewer. The faceting machine is used to hold the stone onto a flat lap for cutting and polishing the flat facets. Rarely, some cutters use special curved laps to cut and polish curved facets.

K2 granite is named after a mountain in the Karakoram Range near the border between Pakistan and China. K2 is the second-highest mountain in the world. The azurite granite is found in colluvium near the base of the mountain. It is in a very remote area visited by very few people.

“K2 Granite,” also known as “K2 Jasper” and “raindrop azurite,” is an extremely interesting rock and lapidary material from the Skardu area of northern Pakistan. It is like an eye magnet for anyone who sees it for the first time. It is a bright white granite that contains sharply contrasting orbs of bright blue azurite. The azurite orbs range from a few millimeters up to about two centimeters in diameter. On a broken surface or on the surface of a slab, the blue orbs look like drops of bright blue ink that splashed onto the rock. Upon closer examination, however, you will see that they are actually spherical in shape.

K2 granite cuts, tumbles, and polishes beautifully. Due to its high feldspar content, it can be easily cut with a lapidary saw and shapes quickly on a diamond wheel. Although azurite has a Mohs hardness of 3.5 to 4, the blue dots have the same cutting and polishing properties as the surrounding white granite.