Carat is the term used to describe the weight of any gemstone, including diamonds. Although the
definition of a carat has changed over time, since 1913 the international standard has been 200 milligrams, or 1/5 of a gram. Often, jewelers describe
carats in 1/4 increments.
In jewelry pieces with more than one diamond, the carats may be described in terms of total carat weight (TW). This is the
combined total weight of all the stones in the piece.
Diamonds can range in size from a fraction of a carat to several carats. Given the rarity of large stones, however, the price
increases rapidly with size; therefore, a single 2-carat diamond will cost much more than two 1-carat diamonds. Very large diamonds with good color and
clarity are very rare.
Expect to pay a premium for stones that are above a full carat weight. For example, a .95 carat diamond will cost a bit more than
a .90 carat stone.
Because round brilliant cuts follow exact standards, you can make a good estimate of the carat weight of the stone based on the