Check out Ultimate Equipment pg 388-390 for Appendix 2: Gems and Jewelry.
What were they smoking when they wrote this? Its super convoluted, and has some weird chart stuff.
- When making simple jewelry w a tier 1 gem increases the value by ×5 (same w tier 3 and 5)
- Making simple jewelry w a tier 2 gem increases the value by only ×2 (same w tier 2, 4, and 6)
- But making ornate jewelry from any tier is a ×10 increase.
Why would you ever make simple jewelry w the even tiers?
- Working unworked gems doubles their value for a 50% profit, using simple rules.
- Making jewelry uses the Craft rules, costing 1/3 for the raw materials. But as w gems, they sell at full value, this is written in the early part of that Appendix. Which gives you a whopping 66% profit. Thats unless you have to also buy the jewelry or gem separately, very confusing.
- Other forms of mundane crafting is only a 16% and magical is a 0%, without tricks.