Buying Guide

Diamond Carats: A Primer on Weighing Diamonds

Majestic Collection 5.03 ct. t.w. Diamond Halo Ring in 18kt White Gold. #933652

Diamond shopping on your mind? It's a good idea to familiarize yourself with the four C's of a diamond: cut, clarity, carat, and color.

What is a Carat?

Carat is the globally recognized standard for measuring the weight of diamonds. The name carat comes from Medieval French, Italian, Greek and Arabic influences, referring to both the carob bean and small weight. A carat is precisely 1/5 of a gram, so a five-carat diamond would weigh one gram.

A larger carat weight bumps up the price of the stone since large-sized sparklers are rare and valuable. However, it's important to remember that two diamonds with equal carat weight can significantly vary in price, depending on the other three factors—color, clarity, and cut. A large diamond is definitely a status symbol, but the cut impacts its dazzling sparkle. In fact, a smaller diamond with a well-crafted cut may look more significant and desirable, all thanks to its brilliant gleam.


Diamond Shopping and Sizes

Finding that exceptional engagement ring while staying within your budget requires shopping acumen, and knowing more about diamond sizes can help you balance price with an exquisite stone selection. "Magic sizes" refer to critical weight measures, such as half a carat, three-quarter carat, and one carat. People love flaunting the carat weight of the diamond—one carat sounds more appealing than 0.96 carats. This desirability makes diamonds with weights of half, three-quarters, and one carat sell faster, making them harder to obtain.

If you're looking to save money while buying a diamond ring, skip the magic sizes and instead go for off-sizes. There's little difference between a 1.99-carat diamond and a 2-carat stone, but the 2 ct. stone will often be more expensive since it falls into a "magic size" category. It could help you find that dream ring without breaking the bank! We have a vast collection of diamond rings in a multitude of sizes to help you find that glittering piece. Our collection features a spectacular range of high-quality diamond jewelry designed to make you look and feel fabulous.

Below is a diamond carat size chart with some of the "magic sizes."

Carat Size mm Size
0.25 ct 4.1mm
0.50 ct 5.0mm
1.00 ct 6.4mm
1.25 ct 6.9mm
1.50 ct 7.3mm
1.75 ct 7.7mm
2.00 ct 8.1mm

What is a 1-Carat Diamond Worth?

In general, 1 ct. diamond costs vary by thousands of dollars, depending on other parameters of the jewel. A round-shaped, 1-carat solitaire measures approximately 6.4mm in diameter. While this may seem small, a well-cut, one-carat rock with a brilliant sparkle looks visually bigger than its carat weight and draws focus with its sparkling shimmer.


Difference Between Karat and Carat

Though they sound the same, there's an ocean of difference between karat and carat! Carat is the unit of weight for gemstones like diamonds, while karat is a measure of the purity of gold. 24-karat is the purest form of gold. But pure gold is incredibly soft, so it is rare for jewelers to craft pieces in solid 24kt gold. The addition of other metals makes gold tougher and lends it a heavenly hue. Jewelers then use this alloy to create beautiful works of gold jewelry. So, a 14-karat gold ring consists of 14 parts gold and 10 parts of some other metal, like copper or nickel.

Mixing in more metals lowers the karat of gold and further reduces the price. Low-karat pieces feature excellent durability and can stand up to wear and tear—an ideal pick for everyday wear or if you lead an active lifestyle.


Diamond Buying FAQs

Since diamonds can be an expensive investment, it's important to have straightforward answers to all of your questions. We've put together a list of FAQs to make diamond shopping more convenient.

How can I tell if a diamond is authentic?

To ensure you're buying only genuine diamonds, shop only from a reputable jewelry retailer such as Ross-Simons. We've been a highly trusted jeweler since 1952, selling superior-quality diamond jewelry that's 100% authentic. Our expert gemologists guarantee the accuracy and quality of the gemstones we offer. Some of our larger diamonds have a certification from an independent laboratory, which confirms their authenticity.

Is carat the most important diamond attribute?

The four C's of diamonds come together to create a stunning gem. All four characteristics determine the quality, size, and sparkle of the diamond. Since carat directly impacts the size of the diamond and its visual appeal, it's considered the most significant feature of the stone. A larger carat size doesn't guarantee the most beautiful piece—it's all about the balance of the four C's that'll help you find the perfect diamond.

What are some tips to keep in mind when buying a diamond?

When shopping for that magical diamond ring, it's essential to pay attention to the stone setting. Certain designs make the diamond look bigger than it actually is—a total win for the buyer. A halo setting, for example, exemplifies this appearance with tiny diamonds encircling the center rock, making the big central stone appear even larger. You can also consider buying a thinner band to highlight the diamond and make it appear more substantial. When purchasing diamonds, the most crucial thing to bear in mind is that two diamonds of the same carat weight may look different depending on the shape, cut, quality, and setting.

If you're looking for an affordable diamond, try checking for eye-cleanliness, which essentially means there are no imperfections visible to your eye. The stones may have inclusions but otherwise appear perfect without the use of a magnifying lens.

What's the best shape for diamonds?

Round diamonds are a classic pick and an all-time favorite with women everywhere. They dazzle beautifully in a variety of settings. If your special someone loves fancier styles, try cushion, oval or pear-shaped cuts.