"Tw" is an abbreviation for total weight in regards to diamond carats. Online, "tw" might be used to describe the total carat weight of all diamonds included in a piece of jewelry.
Frequently Asked Questions
Carat weight can appear differently across different diamond shapes such as round brilliant, princess, pear, oval, cushion, marquise, emerald, radiant or heart. A diamond may have a higher carat weight without appearing larger and two diamonds of the same carat weight can vary in size if one is cut deeper than the other. In other words, it is important to note that carat weight does not necessarily denote size.
Diamonds are measured in carats, which indicates the weight of a diamond, not the size. Tiffany measures diamonds to 1/1000th of a carat; one carat equals .20 grams.