I have a small SharpStone 2.2" black and I love it, if you smoke a lot is a great invest and you will have all kief at the bottom

I got mine here (depending on the size it's like 30 bucks w/ shipping) eBay Store - ZIBHEAD: GRINDERS: 4 PIECE SILVER SHARPSTONE HERB GRINDER MAGNETIC 1.5



Also after grinding the weed it will burn (or vaporize) really easy