What is diamond carat and why is it important?

Diamond carat is important because it directly impacts a diamond’s value, appearance, and overall appeal. As a measurement of weight, carat helps buyers understand a diamond's size relative to other stones. While carat alone isn't the only factor of the diamond buying guide to determine beauty—factors like cut, clarity, and color are equally crucial—it often influences the price significantly. Understanding carat weight ensures you can balance size with quality to find the perfect diamond for your preferences and budget.

Carat is Weight, Not Size

Diamond Carat Explained: One carat equals exactly 0.2 grams (or 0.007 ounces) – roughly the weight of a single grain of rice. Or as the AGS puts it, to get 1 pound of diamonds, you would need over 2,265 carats! 

It's important to understand that two diamonds with the same carat weight can appear completely different in size and shape, depending on their cut and proportions.

Pro Tip: Many people mistakenly believe that "carat" refers to a diamond's size. In reality, carat is a precise measurement of weight, not its dimensions.

To give you an idea of how big a 0.5 CT, 1 CT, 2 CT, and 3 CT round brilliant diamond appears on a hand, let's look at their relative sizes:

• 0.5 CT: This size is typically just slightly wider than the width of the gold band. 

• 1 CT: A 1-carat round brilliant diamond usually covers about a quarter to a third of the finger. 

• 2 CT: A 2-carat diamond often covers about half the width of the finger.

• 3 CT: A 3-carat diamond typically covers just over half of the finger width, making it a bold and attention-grabbing choice.

 

 

What is Diamond CT TW?

 
CT stands for "Carat," and TW stands for "Total Weight." This abbreviation refers to the combined carat weight of all diamonds in a piece of jewelry. The distribution of the total weight can vary depending on the design, so it's always good to ask for specifics when buying.

Example: If you purchase a ring labeled as 1.16 CT TW, it could mean the ring has a 1-carat center stone and 0.16 carats of smaller halo diamonds surrounding it. 

 

What Is a Diamond Cent?

A "cent" in diamond terminology represents one-hundredth of a carat, allowing for incredibly precise measurements. These are also often referred to as "points."

Carat vs. Cent: Both diamond carat and cent describe the weight (not the size) of a diamond. One carat equals 0.2 grams (or 0.007 ounces), so one cent weighs 0.002 grams (or 0.00007 ounces). 

 

Karat vs. Carat: Clearing the Confusion

Diamond carat and gold karat are two completely different things, though they are often confused due to their similar pronunciation.

Carat: A carat measures the weight of a diamond or gemstone, with 1 carat equaling 0.2 grams. For example, a diamond can range from small sizes like 0.25 CT (a quarter carat) to larger, more luxurious sizes like 4 CT or beyond. Carat weight is a key factor in determining the value and appearance of a diamond but does not measure its size, which depends on the stone's cut and proportions.

Karat: A karat measures the purity of gold in an alloy. Pure gold is 24K (24 karats), meaning 100% gold. Lower karat gold, like 10K or 14K, contains a mix of gold and other metals, making it more durable but less pure. For example, 14K gold is 58.3% pure gold, while 18K gold is 75% pure.

 

Why is "Carat" called Carat?

What does "diamond carat" mean, and where does the name come from?

Fun Fact: The term "carat" has a fascinating origin! It derives from the carob seed, which ancient traders used as a standard unit of weight for precious stones. Carob seeds were prized for their remarkable consistency in weight, making them an ideal natural measuring tool long before precise scales were invented.

 

Diamond Carat size Chart

The size of a 1-carat diamond can vary depending on its cut. For example, a round brilliant diamond with an excellent cut typically measures about 6.5 mm in diameter. In contrast, a 1-carat marquise or oval-cut diamond might appear larger because of its elongated shape, even though they weigh the same.

Size Chart and Calculator

Below is a diamond carat table comparing different shape sizes in mm to carat.

Diamond Carat vs mm

 

 

Expert Tip: To make your diamond look bigger without increasing the price, consider choosing shapes like oval or pear. These cuts maximize surface area, giving the illusion of a larger diamond compared to a round brilliant of the same carat weight. Additionally, opting for a halo setting or a thin band can enhance the diamond's perceived size while staying within your budget.

 

Diamond Carat and Weight

Below see a table showing diamond carats and their according weight.

Fun fact: To get 1 gramm of diamond, you need a diamond with 5 carat total weight.

Diamond carat vs gramm and ounces

Fun fact: To get 1 gramm of diamond, you need a diamond with 5 carat total weight.

Diamond Carat and Pricing

Lab-created diamonds typically cost 30-50% less than natural diamonds of comparable quality. Here's a price guide for round brilliant created forever lab diamonds set in white gold:

Did You Know: Lab diamonds offer the same physical, chemical, and optical properties as mined diamonds, but at a more accessible price point.

 

The 4C's: Putting Carat in Context

 

While carat weight is an important factor when choosing a diamond, it’s just one of the four critical qualities known as the 4Cs: Carat, Cut, Color, and Clarity. The relationship between carat and the other Cs is vital in achieving a balanced, stunning diamond. 

• Diamond Carat and Clarity: As carat weight increases, clarity becomes more critical since inclusions and imperfections are more visible in larger diamonds.
• Diamond Carat and Cut: The diamond’s cut plays a significant role in how well it reflects light, enhancing its brilliance and making a larger diamond appear even more captivating. A diamond with a great cut quality can appear larger.
• Diamond Carat and Color: Color becomes more noticeable in larger diamonds, making it essential to choose a stone with minimal color tints to maintain its desired sparkle and aesthetic appeal.

Expert tip: Each of these Cs works in harmony to create the overall beauty of your diamond, proving that carat weight alone doesn’t define its quality.

 

Lab-Created Diamonds & Carat: Specific Insights

Lab diamonds have unique Advantages:

• Consistent quality

• More affordable

• Environmentally friendly

• Ethically sourced

Lab diamonds can be created with extraordinary precision, often with less variation in carat weight compared to mined diamonds.

Lab diamonds are "real diamonds":

1. Are lab diamonds as durable as natural diamonds? Yes! They have identical physical properties.

2. Can you tell the difference between lab and natural diamonds? No, not with the naked eye. Only specialized equipment can distinguish them.

 

 

Frequently Asked Questions