Well, if you go to itemtypes.txt and set the magic column to 0 and the rare column to 1 (I think...either that or set both to 1...I don't have my file handy)...jewels will be able to spawn as rares. But I don't think they'll spawn as rare in shops...only if included in the gamble screen (which will still be a rare event) or if they drop from a monster and end up being rare.If you want it to always be rare, you'll have to make a recipe that give you rare jewels as an output...after you make it possible for them to be rare in itemtypes.txt
In my mod, I simply cloned the jewel to make a new one in misc.txt, gave it a new itemtype with that allowed for rare-ness, and then made a cube recipe that turned normal jewels in the new type and alway makes them come out rare.
That's the only way I know of to ensure that they come out rare.
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- JEFF
"A hero is no braver than anyone else. He is only brave five minutes longer."
For my latest mod (for LoD/expansion), download Version 1.0 of Sanctuary in Chaos - Or for old stuff (for classic D2), visit my orignal mod site at www.planetdiablo.com/sanctuary