Carat Weight	Variance Range
< 1 carat
1/20 carat	.04-.06
1/10 carat	.085-.11
1/8 carat	.115-.14
1/6 carat	.145-.17
1/5 carat	.18-.22
1/4 carat	.23-.28
1/3 carat	.29-.36
3/8 carat	.37-.44
1/2 carat	.45-.57
5/8 carat	.58-.68
3/4 carat	.69-.79
7/8 carat	.80-.94
1 carat	.95-1.11
1/5 carats	1.18 - 1.22
1/4 carats	1.23-1.28
1/3 carats	1.29-1.36
3/8 carats	1.37-1.44
1/2 carats	1.45-1.57
5/8 carats	1.58-1.68
3/4 carats	1.69-1.79
7/8 carats	1.80-1.94
2 carats	1.95-2.11
1/8 carats	2.115 - 2.14
1/6 carats	2.145 - 2.17
1/5 carats	2.18 - 2.22
1/4 carats	2.23 - 2.28
1/3 carats	2.29 - 2.36
3/8 carats	2.37 - 2.44
1/2 carats	2.45 - 2.57
5/8 carats	2.58 - 2.68
3/4 carats	2.69 - 2.79
7/8 carats	2.80 - 2.94
3 carats	2.95-3.11
1/8 carats	3.115 - 3.14
1/4 carats	3.23 - 3.28
1/3 carats	3.29 - 3.36
3/8 carats	3.37 - 3.44
1/2 carats	3.45 - 3.57
5/8 carats	3.58 - 3.68
3/4 carats	3.69 - 3.79
7/8 carats	3.80 - 3.94
4 carats	3.95-4.11
1/8 carats	4.115 - 4.14
1/6 carats	4.145 - 4.17
1/5 carats	4.18 - 4.22
1/4 carats	4.23 - 4.28
1/3 carats	4.29 - 4.36
3/8 carats	4.37 - 4.44
1/2 carats	4.45 - 4.57
5/8 carats	4.58 - 4.68
3/4 carats	4.69 - 4.79
7/8 carats	4.80 - 4.94
5 carats	4.95-5.11
1/8 carats	5.115 - 5.14
1/6 carats	<5.145 - 5.17
1/5 carats	5.18 - 5.22
1/4 carats	5.23 - 5.28
1/3 carats	5.29 - 5.36
3/8 carats	5.37 - 5.44
1/2 carats	5.45 - 5.57
5/8 carats	5.58 - 5.68
3/4 carats	5.69 - 5.79
7/8 carats	5.80 - 5.94
6 carats	5.95-6.11
1/8 carats	6.115 - 6.14
1/6 carats	6.145 - 6.17
1/5 carats	6.18 - 6.22
1/4 carats	6.23 - 6.28
1/3 carats	6.29 - 6.36
3/8 carats	6.37 - 6.44
1/2 carats	6.45 - 6.57
5/8 carats	6.58 - 6.68
3/4 carats	6.69 - 6.79
7/8 carats	6.80 - 6.94
7 carats	6.95-7.11

Diamond Carat, Clarity, Color, and Cut

The 4Cs are a way to compare diamond quality and value. Each "C" has its own grading scale for evaluating quality. Explore them below.

People often mistake carats as a measurement of size, but they actually measure approximate weight (CTW = Carat Total Weight). Typically, a heavier diamond appears larger, but size isn't everything. Two diamonds of equal carat weight can have significantly different value when the other Cs are considered.

	Carat Weight	Millimeter Size (approximate)	Millimeter Size(approx.)
	0.05 ct	2.5 mm
	0.25 ct	4.1 mm
	0.50 ct	5.2 mm
	0.75 ct	5.8 mm
	1.00 ct	6.5 mm
	1.25 ct	6.9 mm
	1.50 ct	7.4 mm
	2.00 ct	8.2 mm

Like any rock or mineral, diamonds can have flaws. Choosing a diamond with a difficult-to-detect inclusion or blemish can be a great way to save on cost without sacrificing beauty.

The GIA Diamond Clarity Grade scale has 11 grades in all. Most jewelry stores carry VVS as their highest grade. VS or SI are considered by most to be "fine quality" diamonds.

	Grade	Description
	F	Flawless inside and out
	IF	Internally flawless — blemishes on the surface but not inside the diamond
	VVS1, VVS2	Very, very slightly included
	VS1, VS2	Very slightly included
	SI1, SI2	Slightly included
	I1, I2, I3	Included and detectable with the eye

Diamonds come out of the earth in many different colors. The market has traditionally valued white diamonds higher than others, and the grading scale offers five groups of 23 letters to reflect that.

	Grade	Description
	D	Top of the scale — colorless, rarest and most expensive
	G	Near colorless
	I	Still appears white, but more affordable
	J	Human eye begins to detect a yellow tint
	Z	Unmistakably yellow in color

Cut refers to a stone's shape, facet, and polish. Sometimes diamonds are cut so they're heavier, fetching more value for their carat weight. Sometimes they're cut to hide or minimize inclusions by expert diamond cutters skilled at bringing the brilliance out of each diamond they work with.

	Grade	Description
	EX	Excellent
	VG	Very Good
	G	Good
	F	Fair
	P	Poor

Variance Chart

Diamond Carat, Clarity, Color, and Cut

Carat

Clarity

Color

Cut

London Blue Topaz Ring 1/20 ct tw Diamonds 10K Yellow Gold