It's possible to have a 1ct stone run you 20,000 + if it were to be colorless and FL or IF
The diamond color grades are as follows:
D, E, F: Colorless. Loose diamonds appear colorless.
G, H, I, J: Near Colorless. When mounted in a setting may appear colorless to the untrained eye.
K, L, M: Faint Yellowish Tint. Smaller diamonds look colorless when mounted. Diamonds of 1/2 carat or more show traces of color.
N - R: Very Light Yellowish Tint and
S - Z: Tinted Light Yellow. These diamonds show increasingly yellow or brownish tints and appear very "off-white".
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The diamond clarity grades are as follows:
FL: Flawless. Cannot be seen with a 10X diamond loupe.
IF: Internally Flawless. Has tiny nicks or scratches that can be polished out.
VVS1, VVS2: Very, Very Slightly Included. Very, very difficult for a qualified observer to see under 10X magnification.
VS1, VS2: Very Slightly Included. Very small inclusions, very difficult to see by a qualified observer.
SI1, SI2: Slightly Included. Can be seen fairly easily by a qualified observer with a 10X loupe, and in some cases without magnification.
I1, I2, I3: Imperfect. Inclusions can be seen with the naked eye, but can be desirable stones at a much lower cost if they are brilliant and lively. Because I3 is the lowest grade used, be on the lookout for industrial grade diamonds not suitable for jewelry that have been classified I3.
