A gem cutter is the profession of a dwarf whose highest skill is in gem cutting. (Though if they have they also have a relatively high level gem setting they will have the profession of jeweler.) A high level of gem cutting allows a dwarf to cut gems faster, and results in higher quality large gems and gem crafts. The skill of a gem cutter does not affect the amount of gems that are turned into large gems, just the quality of these gems. 5% of all rough gems will be cut into large gems or crafts (with large gems being twice as common), and 33% of all raw glass will be cut into large gems (but never crafts).