For your gem needs see our Recommended Suppliers. Some colors produced by irridation, common. Laser drilled to remove inclusions, common. Cracks filled with glass, occassional.
Diamonds are our most popular gem.
They have great brilliance, plus the delightful quality know as fire, or dispersion. Diamonds are graded into dozens of categories. While this is helpful to the professional, it can be confusing to the average consumer. I especially feel for the young couple looking for their first diamond engagement set. They want to gather enough information to make an intelligent decision, but can be overwhelmed by all the data thrown at them.