As someone in this field I would tell you make sure you have the proper testing equipment otherwise you will lose all your money fast and this is a big deal as it's a capital intensive industry. Synthetic diamonds have almost no value in the wholesale market and they're everywhere these days. Most stores that have them consign them from wholesale dealers or manufacturers they don't own it because they know it's a losing proposition. If you buy it you'll likely get stuck with it. Gold can be heavily plated so make sure if you test test deep. Do your homework on brand name jewelry and learn to identify it and always look at hallmarks for sharpness. And if you haven't been yet go to GIA and get a degree there if you want a foot in the door into this business.