I would like to know where I may purchase 20 princess cut diamonds(ranging from .1 to .07 with a total carat weight of approximately 1.72) and 16 round brilliant cut diamonds (.06 to .03 with a total carat weight of approximately .72) to be used in a platinum engagement ring. The diamonds should be well proportioned, matched, graduated(sizes as listed above), G, SI2. I would like to purchase the stones at the best possible wholesale price.