The purpose of the 4cDiamond app is twofold – to provide you with information on tradeoffs for choosing different values of the 4Cs, and to estimate the value of the resulting diamond. The overwhelming majority of the price of a diamond ring is the cost of the diamond itself (the metal ring and setting add little to the total price), and in our experience proper knowledge of tradeoffs and value can save customers substantial amounts on the price of a diamond they would have otherwise purchased at unnecessarily high C levels, or be able to purchase a larger carat diamond with imperceptible-to-the-naked-eye differences in the other three Cs (cut, color and clarity).
As with any estimation, there will always be some error in the estimate, but we try to keep this to the minimum.
Also, as with estimating the value of an extra bathroom or bedroom in a house in a particular neighborhood, estimates are only as good as available sales data in that neighborhood, or available diamond price data. We use frequently updated online diamond prices for our estimates. You should expect to pay more than our estimated price if you purchase the same diamond from a physical store, and the difference will depend on how much of rent and other expenses the store is paying.
Currently our app is only for round diamonds, the most common diamonds sold by far; and only uses online price data in the United States.