Unlike a closing quotation on a typical commodities exchange, the prices recorded in the Rapaport Diamond Report are not actual transaction prices. Rather, they are the Rapaport Corporation's subjective calculation of the "high asking" price, generally 15-30 percent above the actual transaction price, for various sizes and grades of polished stones. One explanation for the markup is that it enables retailers to quote list prices to consumers who think they are getting a bargain when they buy below it.

XREF: Connects to retail pricing psychology — the anchored list price that makes discounts feel like bargains — a common tactic in many industries.

Lisa Bernestein, Opting out of the Legal Sys…, loc. 30