A few questions ( may contain spoilers)

I read about all the equipment over at www.gamebanshee.com. There are some very nice items indeed One nice item tho, ring of wizardy, is attainable by two ways. If your main is mage your apprentices make it for you in P. Sphere or you get from one of the harpers when Jaheira brings you back. I have killed the harpers when they wanted to imprison me but didn't get a ring. Does Jaheira bring me back here one more time or is there something wrong?

All these gems I get, I sell the ones which have value less than 100 and keep the rest. I'm afraid of selling a good one than end up needing it for something in the future(I know about the rogue stone, no way I'm selling it!). Spoil me please and tell me if I need to keep any of them.

Hrmm I'm sure I had one more question..

Oh and I got a nice necklace from Aran. The one protects against level drain and guess what, my monk can use it, hehe those pesky vampires are gonna pay back! =)

There shall be a ring a wizardy on a spellcaster, just loot
them carefully and you'll find it.

The only normal gems you need are 1 Diamond and 1 Bejuril to upgrade the Horn of Valhalla. Speak to the merchant under the picture salesman in Waukeen Promenade. Other gems, like the light gems in the Shadow Dungeon, you can't sell anyway, so don't worry. At worst you can always buy/steal them back later