I want to put the 2.7crt tanzanite gemstone on a necklace, one to give to my girlfriend as an anniversary gift and two as an investment of course. I was thinking a nice but simple 18k white gold necklace. I want it to be elegant but nothing over the top. I was wondering if you could give me an estimate of what the price would be for a necklace of this sort and if you can recommend any specific jeweler. Thanks