Turquoise by nature is a relatively soft, porous stone, and it can vary greatly in its quality. Only rarer high-grade turquoise is actually dense enough that it can be cut and shaped without damaging the stone. Softer turquoise has to be treated in some way in order for it to be made usable. Therefore, the majority of turquoise has been enhanced in some way. The resulting piece of turquoise is then much stronger and easier to cut, polish, and set by a jeweler without risk of breaking.