Choosing the Best Colored Gemstones for Engagement Rings

Colored Diamonds

Put a twist on tradition with a colored diamond. Diamonds have some enviable properties that help make them the top-selling gemstone for engagement rings. With a hardness of 10, diamonds resist scratches better than any other gemstone. That quality is paramount for a ring stone. They also have extraordinary brilliance or "brightness" and dispersion, the capacity to turn white light into flashes of color or "fire." (However, other gemstones can actually outperform diamonds in that regard).

Roughly 1 in 10,000 diamonds exhibits natural color. Those with the most intense colors are prized more highly and, thus, cost more. Colored diamond options include bold canary yellow, sparkling pink, pastel green, eye-catching black, and champagne. Elegant blue diamonds rank among the most expensive.

Sapphires

Sapphire has a reputation as the gemstone of royalty. You don't have to go back to days of yore to see evidence of that. Kate Middleton, the Duchess of Cambridge, received a sapphire engagement ring that once belonged to Prince William's mother, Princess Diana. Other notable royalty and celebrities, like the Empress Josephine, Penelope Cruz, and Elizabeth Hurley, had gemstone engagement rings that included sapphires.

Although popularly associated with the color blue, sapphires come in every hue (except red). Furthermore, these gems show pleochroism, two different colors, depending on the viewing angle. Some rare specimens can also change color, depending on the light source. Star sapphires, another rare variety, display a stunning star-like optical effect known as asterism.

With a hardness of 9, sapphires are among the hardest natural non-diamond gems. They make excellent jewelry stones, especially for engagement rings. Sapphires are some of the most sought after and expensive gems in the world.

Emeralds

Want more royal gemstone options? Consider emeralds, the "jewel of kings." Reputedly Cleopatra's gem of choice, emeralds come in gorgeous greens, from light to a deep, dark shade.

With a hardness of 8, emeralds can resist scratching well but do require special care. An emerald's jardin or "garden" of inclusions and fractures makes every stone unique. However, they can also affect clarity and durability. As a result, emeralds commonly receive oil and filler treatments, which may need to be reapplied over time. Never clean emerald jewelry with ultrasonic, steam, or boiling systems.

Choosing emeralds takes extra effort, but their stunning color and rarity make them particularly prized options for gemstone engagement rings. Before making your decision, read our emerald buying guide and ring stone guide to learn more.

Rubies

A ruby will make a sizzling statement when set in an engagement ring. Rubies are the coveted red variety of corundum. All other colors of gem-quality corundum are considered sapphires. It shares the hardness and durability of sapphire, although ruby tends to receive more treatments and enhancements. "Pigeon blood red," a slightly purplish red with a medium-dark tone and vivid saturation, is the most sought after ruby color.

Ruby's durability, rarity, and associations with love and the heart make it a fitting (albeit expensive) choice for gemstone engagement rings. A centerpiece ruby surrounded by diamonds would make a one-of-a-kind ring.

Amethysts

A pretty and popular alternative to diamonds, amethysts make striking gemstone engagement rings. This lovely variety of quartz shows colors ranging from light lavender to deep purple. They have a hardness of 7 and no cleavage planes, making them difficult to scratch or break. (Incidentally, a gem needs a minimum hardness of 7 to avoid scratches from a very common hazard: household dust).

Both light "Rose de France" and dark purple, red flashing "Siberian" amethysts have their aficionados. Either color or any between would make beautiful jewelry pieces. At first glance, a gem with symbolic connections to calming passions might seem an odd choice for an engagement ring. On the other hand, this could perfectly represent a love ready for an enduring, deeper commitment.

Tourmalines

The tourmaline gem family includes many species in many colors. Some, like the aptly named watermelon tourmaline, even display two or three zones of distinct colors. Like quartz, they have a hardness of 7 and no cleavage, making them very durable choices for engagement rings. All tourmaline varieties have a vitreous luster. This means their surfaces look like glass when light hits them. Some varieties also change colors under different light sources, and others show a cat's eye optical effect known as chatoyancy.

Some of the most popular tourmaline varieties include:

• Green or verdelite tourmalines, readily available and affordable.
• Chrome tourmalines, rarer green tourmalines with emerald-like color, colored by chromium.
• Rubellite tourmalines, beautiful raspberry red to deep red gems.
• Blue or indicolite tourmalines, gems with light to dark tones and moderately strong saturation, generally more expensive than green verdelites.
• Paraíba tourmalines, rare and expensive, almost neon blue tourmalines, colored by copper.

Check out our tourmaline buying guide and ring stone guide to learn more.

Citrines

You can easily see why citrine has become a popular choice for gemstone engagement rings. Its colors can range from light, lemony yellow to golden and even a champagne brown. So-called "Madeira" citrines show a rich, orange color with red flashes and command the highest prices. Citrines have the durable physical characteristic of all quartz varieties, like amethyst. Thus, they make excellent ring stones.

Garnets

Although commonly associated with the color red, garnet gems come in more colors than perhaps any other gem species. (In fact, garnet is a family of gems, like tourmaline, and includes many different species). You can also find white, brown, orange, yellow, green, purple, and even very rare color change stones. Garnet species range from a 6.5 to 7.5 hardness and have no cleavage. Whether cut as cushions, hearts, or rounds, they make excellent engagement ring stones.

• Rare, green demantoid garnets are highly prized. They have greater brilliance and dispersion than diamonds.
• Tsavorite garnets show an emerald-like color. However, they have more durability, brilliance, and dispersion that emeralds. In smaller sizes, they are also easier to find on the market.
• You can't get more orange than very rare mandarin garnets. This eye-catching gem has wonderful brilliance.
• Malaia or malaya garnets come in many shades of red and orange, including pink and peach. Some stones also show color change and, when properly faceted, scintillating or sparkling red flashes throughout the gem.
• Rhodolite garnets show a ruby-like purplish red color. Some gems may change colors from purplish red in incandescent light to blue in daylight.

Aquamarines

The light blue to blue-green shades of aquamarine can bring a dream-like quality to engagement rings. These gems can look great alone or surrounded by diamonds, especially with a round cut. Like emeralds, aquamarines belong to the beryl gem family. They have an exceptional hardness of 7.5 to 8, too. However, aquamarines possess greater durability than their emerald brothers and don't require special care or cleaning.

Although gems with deeper blue tones may cost more, even lighter tones can make beautiful jewelry stones with ocean-like beauty. Some rare aquamarine gems can show asterism and cat's eye effects.

Opals

Looking for a completely different type of engagement ring? Consider an opal gem. They display a unique gemstone optical phenomenon known as play of color. These multi-colored flashes move across the surface of the stone. Opals can also show many different, vibrant body colors as well as unusual patterns with imaginative descriptions, like floral and harlequin. Opals differ so much from other gemstones they have their own distinct terminology and grading system.

Of all the colored gems discussed here, opals require the most care. They have a low hardness of 5.5 to 6.5, which makes them very susceptible to scratching. They also have great sensitivity to sudden changes in temperature. Stories abound of opals cracking when taken from room temperature into a cold winter evening. Opals have a high water content. If they dehydrate, they may "craze" or crack. Thus, these gems have special storage and cleaning requirements.

Opals as ring stones will need protective settings, such as bezels, with metal covering the edges of the stone.

If properly set, whether mounted alone or surrounded by complementary gems, opals will look lovely in engagement rings. Your opal ring will never look like anyone else's.