Dont be fooled into buying diamond dealers that is said to be .25 points. It is NOT a quarter of a carat, and will be so small that it should only be used as accent to other stone or the gold itself.
The range of ideal cut prices can be dramatic depending on the size and quality. For example a half caret brilliant cut round diamond of K color and I1 clarity would cost about $2000 per caret or $1000.
diamond jewelry experts would never attempt to verify a diamonds color in a setting, and would insist on a certified color comparison before attempting to make a fair evaluation, confirming how difficult differences in color grades are to see.