The value of fancy diamonds is determined by theirs grading under the 4 Cs, color, clarity, cut and carat weight.
Because fancy shaped diamond bracelet is not symmetrical like a round loose diamond, a broader range of parameters are needed in regards to proportion.
jewelry in jewelry are the most popular of all gemstones. Their price and rarity is carefully monitored by the major diamond cartels. As a result the price of loose diamond in jewelry is pretty well standardized to size and quality of the stone.