As of August 2014, one carat of peridot, medium to slightly yellowish green, flawlessly cut and free of any visible inclusion is worth $77.47, according to Gemval. The value of peridot is determined by appraising its color, clarity, cut and carat weight.
The most desirable color for peridot is a medium toned, dark green without any gray or brown. This is the standard by which all other peridot is graded by. Peridot's clarity is appraised by counting the number of black mineral crystals in it that are visible to the naked eye. Each inclusion present lowers the overall value of the stone by a percentage.