Sapphire vs Diamond: What’s the Difference?

Sapphire and diamond differ widely in prices, origins, appearance, meaning, and durability. These distinct gemstones are both popular choices for engagement rings, wedding bands, and other sentimental jewelry. But how do you choose between them?

In this guide, we’ll outline all the key differences you need to know when shopping for sapphire vs. diamond. No matter your personal preference or unique style, here’s everything you need to know about these two stunning stones.

What is a Sapphire?

Sapphire is a precious gemstone and member of the corundum family. While sapphire is famous for blue hues, it can come in almost any other color, except for red.

Take a deep dive into the different types of sapphire in our sapphire guide.

What is a Diamond?

Diamond is the hardest natural material on earth. The traditional engagement ring choice is a white diamond, but diamonds can also come in champagne, yellow, or other ‘fancy’ colors.

See all the essential diamond information in one place in our diamond guide.

The Main Differences Between Sapphire and Diamond

1. Price

Overall, natural diamonds are more expensive than sapphires. For both, the cost per carat increases with the total carat weight of the stone. This is because raw diamonds or sapphires large enough to yield a high carat weight stone are exceedingly rare. The gem’s physical characteristics and quality measures, such as clarity and cut, also play a significant role in the stone’s value.

Sapphire can cost as little as $25 per carat, while large, high-quality sapphires can cost over $11,000 per carat. Natural diamonds range from $2,000 per carat to as high as $30,000 per carat. Lab grown diamonds have a more budget-friendly price tag, ranging from $500 to $1000 per carat. Depending on the stone’s size, origin, and quality, the price difference between diamond and sapphire can be quite large.

2. Appearance

Inclusions

Both sapphire and diamond are naturally found with inclusions, tiny abnormalities or foreign minerals included in the gemstone. Virtually all sapphires and diamonds have inclusions, but they may not be visible to the naked eye. 

While inclusions are often called “flaws”, they can also produce stunning and desirable effects. Sapphires with many inclusions take on a luxurious “silky” texture. Kashmir sapphires are famous for this silky quality. Heavily included diamonds can take on a galaxy, salt-and-pepper, or rustic appearance.

Sparkle

A stone’s sparkle is measured by its refractive index: how much a light is reflected or passes through a material. Diamonds have an exceptionally high refractive index, giving them their signature bright white sparkle and timeless elegance. When the white sparkle from a diamond reflects into colorful flashes, it’s called “fire”.

Sapphire has a lower refractive index, making them less sparkly than diamonds. Sapphire has a more subtle, elegant sparkle.

Size

Both sapphire and diamond are measured in carat weight. However, sapphire is denser than diamond. That means a one-carat sapphire will appear smaller than a similarly-cut one-carat diamond.

Color change

While both sapphire and diamond can have colors, sapphires often change color. Many sapphires shift between purple and violet under different lighting conditions, for example, natural light vs white light vs incandescent light. Sapphires that change colors dramatically are highly prized by collectors for their unique appeal.

Diamonds can change color too, but it’s more rare. These stones, called chameleon diamonds, shift colors under U.V. light.

3. Colors

Sapphire is famously blue, but can come in many vivid colors, except for red. That’s because red corundum stones (the mineral sapphires are formed of) are called rubies! They can even mimic diamonds—white sapphires are colorless, making them a popular diamond alternative.

Diamonds are typically colorless, but not always. Naturally-colored diamonds are formed when trace elements interact with the carbon during the diamond’s creation. Peachy or yellow-tinted champagne diamonds are a popular alternative to white diamonds, but diamonds can also be found in other “fancy” colors.

Sapphire is found in the following colors:

- Blue

- Pink

- Yellow

- Green

- White (colorless)

- Purple

- Violet

Some sapphires are comprised of multiple colors:

- Padparadscha (pink, leaning orange)

- Peacock/parti-color (blend of blue, green, and sometimes yellow)

Diamond is found in the following main colors:

- White (colorless)

- Yellow

- Blue

- Pink

- Orange

- Green

- Brown

- Gray

- Purple

- Violet

- Red

- Black

Diamonds can have more than one of these colors, creating subtle hybrid colors like “grayish purple” or “pinkish orange” diamonds.

4. Hardness

Both sapphire and diamond are measured on the Mohs hardness scale. This scale ranges from 1 (soft talc) to 10 (diamond). If you scratch two minerals together, the harder mineral will scratch the softer one.

Diamond is the hardest gemstone on earth, making it a popular choice to represent your enduring love story. Sapphire is nearly as hard as diamonds, clocking in at a 9 on the Mohs hardness scale.

For both sapphire and diamond, inclusions can influence the practical hardness and durability for everyday life. Stones with many inclusions, like silky sapphires or galaxy diamonds, are more susceptible to chipping.

5. Meaning

Sapphire represents nobility, protection, royalty, and faithfulness. Ancient cultures were inspired by the stone’s beauty and durability, and believed sapphire would protect its wearer from harm. This steadfast stone is the perfect gem for a meaningful engagement ring. Sapphire is also the birthstone for the month of September.

Diamond symbolizes strength, invisibility, and eternal love. The Ancient Greeks called diamond “adamas”, meaning “unconquerable”. In medieval Europe, diamonds were worn into battle as amulets of protection. Diamond is also the birthstone for the month of April.

6. Rarity

Sapphires are rarer than diamonds. However, they are still the most common colored gemstone. Certain colors of sapphire are rarer than others. For example, natural unheated blue sapphires with high clarity are extremely rare. Padparadscha sapphires are another rare and unique alternative gemstone.

Diamonds are not rare. Despite their value and durability, they are one of the more common gemstone options. Jewelry-grade diamonds are rarer than raw diamonds. However, at least 133 carats of jewelry-grade diamonds are sold annually.

7. Origin

Sapphire is mined underground, or from alluvial deposits: sediment that is deposited by running water into a stream bed. The leading regions for sapphire mines are Southeast Asia, Africa, Central Asia, Australia, and Montana.

Diamonds are found in two types of environments. Most are found in kimberlites: pipe-like formations created by volcanic activity. Other diamonds are found in alluvial deposits from kimberlite that has been eroded by water.

Different sapphire types and colors are found in different locations. Kashmir is famous for its deep blue sapphires with a silky texture, which were predominantly mined in the late 19th and early 20th centuries. Sri Lanka is famous for its bright pink-orange Padparadscha sapphires, which look like a lotus flower. Learn more about sapphire appearances by origin in our sapphire guide.

Diamonds are mined all over the world. Russia is currently the world’s leading diamond producer. Other top producers are Botswana, Canada, South Africa, and Australia. At Sarah O., all our natural diamonds comply with the Kimberley Process, which aims to reduce the trade of conflict diamonds.

Lab grown diamonds are also a popular and affordable alternative to natural diamonds. If you’re on a tighter budget but still want a gem-quality stone with diamond’s signature sparkle, lab grown is a great choice. Learn more about lab grown diamonds here.

8. History

Sapphire has carried historical significance as a meaningful gemstone since 800 BCE. Over the millennia, cultures across the world have valued sapphire as a symbol of protection and spiritual enlightenment. In the 1980s, sapphire engagement rings saw a surge in popularity when Prince Charles proposed to Lady Diana with a 12-carat blue sapphire.

Diamonds were first found in India, at least 3,000 years ago, and have been treasured as gemstones and adornments ever since. Diamonds were also historically used for engraving because of their hardness.

Diamonds rose in popularity following new developments in cutting and polishing in the 19th century. In the mid 20th century, an advertising campaign by the diamond company De Beers boosted diamonds to new heights.

9. Geology

Sapphire is composed of the mineral corundum, also called aluminium oxide. They can take millions of years to form and are typically found in limestone and metamorphic rocks. Trace minerals within the stone give sapphires their color, from signature blue shades to other colors of the rainbow.

Diamond is composed of pure carbon arranged in a crystal lattice structure. These stones were formed millions of years ago within the earth’s crust.

Choosing Between Sapphire and Diamond

Sapphire is beloved worldwide for its beautiful colors, rarity, and exceptionally durable structure. These stones are highly diverse with many show-stopping variations, like silky blue Kashmir sapphires or sunset-colored Padparadscha, and can even change colors in different lighting.

Diamond is prized for its unmatched durability and timeless brilliance. A well-cut diamond produces eye-catching rainbow fire when the light hits it just right, creating fine jewelry that’s simply captivating. You’ll pay a premium price, but as the hardest substance on earth, diamond is the ultimate symbol of your love.

Whether you choose a diamond or a sapphire, make sure your stone is certified by the Gemological Institute of America to confirm the gem’s authenticity and quality. Purchasing a GIA-certified gem ensures that you’re buying the real deal, just like your true love.

If you’re ready to take the next step towards purchasing your new diamond or sapphire jewelry, check out our collections of sapphire engagement rings and classic white diamond engagement rings. Not seeing a ring that fits your personal style? Book a custom engagement ring consultation to bring your vision to life with Sarah O. today.

Get more gemstone, diamond, and engagement ring tips on the Sarah O. blog.