What does one tenth Carat TW Diamond mean?

Answer 1

The phrase "carat TW" means the carat total weight. This implies there may be multiple diamonds involved in the piece of jewelry and when they are all added together, one-tenth of a carat is their combined weight.

"Carat" is just a diamond industry special word for weight of a diamond stone. One carat is equal to 200 milligrams, or in other words, a 5-carat stone weighs 1 gram. The word "carat" originates from the Greek word kerátion, which means carob beans, which were known in the ancient world for uniformity of their size and weight and were used as a measure of weight for different objects, including gemstones.

In the Far East instead of carob beans jewelers used rice grains to determine the weight of gemstones. Because of this fact, you may occasionally hear some jewelers referring to a 1-carat diamond a "four grainer," which means in the past 1 carat was equal to four grains of rice. The weight of smaller diamonds is often expressed as points, not carats. One carat is equal to 100 points. Thus, for example, a 10-point diamond has the weight of 0.1 carats.