All of them!
Jk, but it's rarer to find pure pretty much anything (unless there's a lot of one kind of gem around a specific area that you happen to be in, in which case it's still rare to find anything else in an abundant pure form) but composite minerals/gems/etc can be just about any color. Diffused red impurities or sulfurs can create a yellow hue. The browns I think (from dirt, rust, minute imperfections, etc) make yellow an incredibly common color here, as opposed to lots of blue or even bright red or true red. For the real thing though?
Idk
Sounds radioactive lol
(like emerald is famously green, and gold is famously yellowish, amber is famously amber, Tiger's eye has a nice yellow/red/gold thing, going on for it, Diamond can create a beautiful yellow/blue light by its prism effect on light, etc)
Anyway
Something broken about yellow in nature?
How about a metallic gem? Tungsten and titanium come to mind, just as like a who knows what's possible, or already out there