Carats versus karats are like apples versus oranges. Both are pronounced just like the vegetable, but couldn’t be more different. All diamonds and gemstones are measured by carats, but what is a carat and what can you compare it to? And so what are karats?
What is a Carat?
Carat (abbreviated as ct.) is a tiny measurement of weight used for gemstones and diamonds. Just to give you a comparison, one carat is 0.20 grams. Carats can also be broken into points. Points are a less well known form of measurement for diamonds and are mostly used between industry professionals, but if you are a visual learner like me, this picture I’m going to paint might help. Think of a carat and a U.S. dollar the same. Just as a penny is 0.01 of a $1.00 dollar, a point is 0.01 of a 1.00 carat.
What Does “TW” Stand For?
Total weight (abbreviated as tw) refers to the total carat weight of a ring. For example, say you’re in a jewelry store and you ask to see a diamond ring that caught your eye from the case. You peek at the tag that reads “1.50ct / 2.00cttw” At a first glance, it may seem like cryptic alien speak, but it actually alludes to two important things. The 1.50ct is the carat weight of the center stone diamond, and the “2.00cttw” is the overall weight of all of the diamonds in the ring, including the center stone. They can't fool you anymore!
How Did The Carat System Originate?
The modern carat weight system we use today has some very unexpected origins. Carat was derived from the Greek word “carob”. What's a carob you ask? They are seeds! (I bet you didn’t expect that.) Carob seeds were used by some of the earliest gem merchants as a way of measuring their stones. People would use carob seeds as a counterbalance because carob seeds were believed to all be universally the same weight. Just imagine buying diamonds based on seeds!
What is a Karat?
Now karats on the other hand are a whole different ball game. While carats, as mentioned before, are used to measure weight, a karat (abbreviated as K) is a measurement of purity. 24k gold is gold in its purest form, or 100% gold. 18k gold is 75% gold and the other 25% are a mix of other metals (called alloys) used to help strengthen the gold to help its durability. Since gold is such a soft metal, the highest recommended karat to use in jewelry is 18k. Although, in Europe, you may see 15K or 17K, and throughout Asia, 24K is popular.
In about 450 words you learned about carats, total weight, karats, and a little history about seeds. I hope all of this newfound knowledge aids you in your diamond buying adventure and possibly a future game of trivia.