Characters with this skill can cut gems given the correct tools and sufficient time, at the rate of D6 stones per day, so long as no stone is worth over fifty Gold Crowns. Stones worth fifty-one to one hundred Gold Crowns each take a whole day to cut. Stones worth over one hundred Gold Crowns each take D6 days to cut.
To determine success or failure, a test should be made against the average of Int and Dex. If successful, the value of the gem is increased by 5% for every point under the requirement rolled on the dice. (So an Int 50, Dex 40 gemsmith rolling 05 would have increased the value by 200%.) If the character is recutting a once-cut gem, the increase in value will be 10%. If the test is failed, the value of the cut or uncut stone is halved and the character must start from scratch working on the smaller stone. Large gems may be split into smaller gems totalling 75% of the original value and jewelry can be broken up or recut, losing 10% of its value.