Educational Home > Diamond Education > The 4 C's > Carat
A diamond's weight is measured in what is known as a "carat." This small unit of measurement is equal to 200 milligrams, and carat weight is commonly expressed in points or fractions. There are 100 points per 1 carat. For example, 0.33 carats is usually expressed as 33 points, or 1/3 of a carat. See the charts below for an idea of the relative size of a diamond according to carat weight.
You can search according to carat weight on Anjolee’s product page under “step 2.” The numbers on the dropdown menu refer to the total carat weight of the selected style.
What does total carat weight mean?
A diamond’s total carat weight is determined by the minimum weight of all the diamonds in a single piece of jewelry. For instance, if a pair of diamond studded earrings has a total carat weight of ½ (.50) carat, then each earring in this pair would have an individual carat weight of ¼ (.25) carat.
The Federal Trade Commission has strict guidelines about the range of carat weight that a fraction can represent. The diamond you purchase may weigh slightly more or less than the fractional weight specified. The chart below shows the satisfactory ranges for carat weights expressed as fractions.
• 1/4 carat total weight may be 0.21 to 0.29 carats
• 1/3 carat total weight may be 0.30 to 0.36 carats
• 1/2 carat total weight may be 0.45 to 0.59 carats
• 3/4 carat total weight may be 0.70 to 0.84 carats
• 1 carat total weight may be 0.95 to 1.10 carats
• 1 1/4 carats total weight may be 1.20 to 1.29 carats
• 1 1/2 carats total weight may be 1.45 to 1.55 carats
• 2 carats total weight may be 1.95 to 2.05 carats
Why is carat weight important?
The carat weight of a diamond is one of the major factors affecting its price (along with cut, clarity and color). Larger diamonds are rarer than small ones, so value increases exponentially for higher carat weights.
How does carat weight affect diamond size?
As diamond’s carat size increases, both the diameter and the depth of the diamond also increase. A 1 carat diamond approximately 6.5mm in diameter will not look twice as wide as a 1/2 carat diamond that is approximately 5mm in diameter. See the chart below for clarification on specific styles and carat weights.