Here are three very different words that are pronounced the exact same way.  So what is the difference? 
 
Karat and carat are two words that are commonly used when talking about jewelry.  Karat measures the purity of gold and carat measures the weight of a gemstone.  A common mistake is using the terms interchangeably. We will examine what each term means in order to understand the difference.
 
Gold is a very soft metal and is often mixed with other metals in order to make it stronger. Karat, which is often abbreviated k. or kt., describes the purity of the gold. Pure gold is 24 karats.  One karat represents 1/24th of the whole.  Any designation that is less than 24 karats means that the gold is mixed with other metals.  As an example, gold designated as 18 karat gold consists of eighteen parts gold and six parts other metal, for a total of 24 parts. Ten karat gold, which equates to ten parts gold and fourteen parts other metal, is the minimum karats which may be considered gold in the USA.
 
A carat is a unit used to measure the weight of a diamond or other gemstones. It is abbreviated c. or ct. One carat is 200 milligrams or 1/5th of a gram.  Now remember, a carat refers to the weight not the physical size of a gem. A one carat denser gemstone would look smaller than one carat of a less dense stone.
 
Historically, these terms are believed to have originated from the carob bean. This bean is a seed pod that has such a consistent weight that it was used to measure the weight of gemstones.
 
What about carrot?  Don't you know? It's Bugs Bunny's favorite vegetable!

 

Illustrated is a ladies ring of tanzanite and diamonds in 18kt white gold. You can see this plus a selection of jewelry and items at our location on Ruby Lane