What is the Difference Between Carats and Karats

Jewelry terminology can feel confusing, especially when two words sound identical but mean completely different things. “Carat” and “Karat” are often mixed up but they measure two completely different things in jewelry.

Carat (with a C) measures the weight of a diamond or gemstone

Karat (with a K) measures the purity of gold in a piece of jewelry

Although they sound the same, one refers to gemstone weight and the other refers to gold content.

What is a Carat?

A carat (ct) is a unit of weight used to measure diamonds and gemstones.

·       1 carat = 200 milligrams

·       1 carat = 0.2 grams (one fifth of a gram)

Carat does not directly measure the physical size of a diamond or gemstone, it measures weight. However, a higher carat weight often results in a larger-looking stone, assuming proportions are similar.

Important to note: Two diamonds can have the same carat weight but look different in dimensional size due to how it is cut.

What is a Karat?

A karat (Kt or K) measures how much pure gold is in a metal mixture.

Gold is typically mixed with other alloys for durability. Karat tells you how much of that mixture is real gold.

Common Gold karat levels

·       10kt gold = 41.7% pure gold (10 parts gold, 14 parts other metal)

·       14kt = 58.5% pure gold

·       18kt = 75% pure gold

·       24kt = 100% pure gold

24kt is pure gold but is soft and not very practical for everyday jewelry.

How Karat Affects Price and Color

When gemstone quality is equal, the price difference in rings often comes down to gold content.

·       Higher karat = more pure gold

·       More pure gold = higher cost

·       Higher karat = richer yellow tone

For example:

An 18kt gold ring will cost significantly more than a 10kt gold ring because it contains more pure gold.

Why Do Carat and Karat Sound the Same?

Both words originate from the Greek word, “keration,” referring to the carob seed, which ancient traders used as a weight comparison for gemstones and metals.

Over time:

·       “Carat” became the spelling for gemstone weight

·       “Karat” became the spelling for gold purity

Clear as mud, but at least now you know the difference!

Frequently Asked Questions

Is carat the same as karat?

No. Carat measure gemstone weight. Karat measure gold content

Is a higher carat diamond better?

Not necessarily. Carat refers to weight, not quality. Cut, clarity, and color also matter.

Is 24KT better?

It is purer, but softer. 14kt and 18kt are often better for everyday wear.

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