I''m going to start looking at loose stones. What is the best strength loupe to use? I notice in jewlery stores they use 10x. Would it be easier to see inclusions, etc. witrh another strength?
Does anyone know where I can go to buy a loupe in Los Angeles? Which manufactuerer?
Dave Atlas at http://www.gemappraisers.com/ sells the loupe you'll need. Don't get over a 10 power triplet, it just makes it harder to focus. The depth of field on a 10 power is perfect for your purposes.
While you're at it, buy an IdealScope ($25) at his site as well, along with a "calibration" cz($5). It is the best tool for the layperson in evaluating the light return performance of diamonds. Great for eliminating poor performers quickly.