anello diamanti vintage

What do the abbreviations TW (Total Weight) and CTW (Carat Total Weight) mean that are found in the certificate of a jewel

Do they have anything to do with the diamond’s “carats”?

The weight of a diamond is expressed in the “carat” unit of measurement, which is one of the most popular parameters, even for those who have no gemological skills.

The carat weight of diamonds is one of the “4 Cs” that make up the stone’s identity card and quickly and uniquely specify its value and size.

The 4 C’s are precisely Carat, Cut, Clarity, Color .

The purest diamond has high purity and no color. A large diamond, with high carat weight but low purity and color will not even remotely have the same value as a diamond of the same carat weight, with more appreciable parameters of purity and color. For this reason, in common jewelry, where the diamond is used as an ornament but is not the protagonist of the work, diamonds of particularly high value are not used, especially if there are many stones.

For this reason, the parameters are described in the certification of the jewel:


TW: total weight of the stones

CTW: total weight of the stones in carats.

DTW: total weight of only diamonds in a jewel.

For example, a trilogy ring can consist of 1 CT of diamonds (DTW): two 0.3 CT diamonds and one 0.4 CT.

Ideally, each of them should be immediately linkable to their certificate to determine the exact value of the jewel.

It is not uncommon to see jewels with high DTW but composed of a myriad of stones of tiny size and low purity (example: pavé settings), which do not present high value on the market precisely because if they were disassembled, they would lose the added value brought by the Brand or from the invoice of the jewel itself.

A tennis bracelet, for example, usually has a high DTW and is made up of numerous diamonds.

The value of a single 1 carat diamond, for example, will never be the same as 2 diamonds of the same or similar purity, color and cut and 0.5 CT each.

Understanding every detail of a diamond and the certificate of a jewel ensures you avoid that the jeweler or trader on duty tries to sell you at a high price pieces with an important design or produced by commercial and industrial brands that once put back on the market could reserve ugly and love surprises. Minimal quantities of gold, small and impure stones but expertly mounted, often give rise to showy jewels but of very little value on the market.