All cut gems start out the same way: as crystals or crystal pieces mined from the earth. In the trade, these raw pieces are known as "rough." Acquiring these is the first step in the gem cutting process. Some pieces of rough, like the spectacular Afghani tourmaline crystal to the left, are works of art straight from the ground and are sometimes used in jewelry as-is. There are many factors which determine the value of a particular piece of rough, and all must be considered carefully when evaluating material. Here is just a partial list:

Color and Clarity - Obviously, the better the clarity and color that a piece of gemstone rough has, the greater the potential value of the finished stone. Unfortunately, these characteristics are more difficult to assess that one might think. In many cases, the outer surface of the stone prevents easy inspection of the interior. Flaws are almost always present at the surface, and they not only obscure the stone's interior, but it is also difficult to determine just how deep those surface flaws go. Judging color in rough gemstones is as much an art as a science, due to the way light behaves differently when simply passing through a stone a single time versus reflecting within it (as in the finished gem). In addition, many gemstones display completely different colors, depending on the crystal axis one looks down! Knowing how these colors will influence the finished stone is crucial.

Shape - Rough straight from the ground is typically just that - rough. It is irregular in shape and must be carefully selected to achieve the desired finished gem shape or the largest possible finished stone. It takes experience and very careful examination to envision how the cut gem will emerge from what, in many cases, looks like little more than a piece of gravel or a shard of glass.