The idea that an engagement ring must have a diamond is a relatively recent convention — and one that a growing number of couples are choosing to set aside. Colored gemstone engagement rings have a long and distinguished history, from the sapphires favored by royalty to the rich rubies of Art Deco design. Today, they're one of the most compelling options for anyone who wants a ring that's truly distinctive.
Sapphires, rubies, and emeralds are the three most important colored gemstones in fine jewelry, and each brings something different to an engagement ring. Here's what to know about all three.
Sapphire engagement rings
Sapphires are the most popular colored gemstone for engagement rings, and they've been for centuries. The most famous example — Princess Diana's sapphire and diamond halo ring, now worn by Princess Catherine — helped cement that association in modern culture, but the preference for sapphires goes back much further.
The practical case for sapphires is strong. They rank 9 on the Mohs hardness scale, making them the second-hardest gemstone after diamonds. A sapphire can handle daily wear without the fragility concerns that come with softer stones. They're also remarkably varied: while deep blue is the classic association, sapphires come in virtually every color — pink, yellow, padparadscha (a rare peach-pink), teal, and even colorless. A colored stone engagement ring doesn't have to mean blue.
What to look for in a sapphire
Color is the primary value driver in sapphires, and within blue sapphires, the most prized shade is a vivid, deep blue with a slight violet overtone — sometimes called "cornflower blue" or "royal blue." Kashmir sapphires are the most historically prized origin, though Burma (Myanmar) and Ceylon (Sri Lanka) stones are also highly regarded. Heat treatment is standard and accepted practice in the sapphire market; untreated stones command a premium.
Ruby engagement rings
Ruby is corundum — the same mineral family as sapphire — colored by chromium to produce its distinctive deep red. Fine rubies are among the rarest and most valuable gemstones in the world; high-quality rubies over 2 carats with no heat treatment routinely exceed the per-carat price of diamonds of equivalent size.
Like sapphires, rubies rank 9 on the hardness scale and are well-suited to daily wear. The challenge with rubies is finding stones with rich, even color and good clarity — inclusions are common, and the best stones (those with the "pigeon's blood" red color and strong fluorescence) are genuinely scarce.
The ruby and diamond combination
Rubies pair exceptionally well with diamonds, which provide contrast and framing without competing with the stone's color. A ruby center stone flanked by diamond side stones or set in a diamond halo is one of the most historically significant ring compositions in fine jewelry — and one that looks as relevant today as it did a century ago.
What to look for in a ruby
The most important factor is color: look for a pure, vivid red without too much orange or purple overtone. Burmese rubies are considered the gold standard of origin. Most rubies on the market have been heat-treated to improve color and clarity; this is standard and does not meaningfully affect value unless you're specifically seeking untreated stones.
Emerald engagement rings
Emeralds occupy a unique position in the gemstone world. Their color — a vivid, saturated green that no other stone quite replicates — is immediately recognizable and deeply associated with luxury. But they require more care than sapphires or rubies, and understanding that going in makes for a much happier long-term ownership experience.
Emeralds rank 7.5–8 on the hardness scale, which is not quite hard by everyday standards. The bigger consideration is their clarity: nearly all natural emeralds have inclusions and fractures (called "jardin" by gemologists) that are visible to the naked eye. This is not a flaw in the conventional sense — it's simply the nature of emerald crystal formation. The trade considers emerald inclusions acceptable in a way that diamond inclusions generally are not, and most emeralds are treated with oils or resins to improve the appearance of surface fractures.
What to look for in an emerald
Color is everything: the most prized emeralds have a pure, vivid green with slight blue overtones and high saturation. Colombian emeralds are the most famous and sought-after origin. Because inclusions are expected, clarity takes a back seat to color and transparency when evaluating quality.
Practical considerations for colored stone rings
One thing to think carefully about with any colored stone engagement ring is the setting style. Prong settings expose more of the stone but can also be more vulnerable to chipping at the girdle. Bezel settings offer more protection, particularly for emeralds. For sapphires and rubies, which are significantly harder, the concern is lower, and almost any setting style works well.
Colored stones also require some care around cleaning. Ultrasonic cleaners, which are commonly used for diamonds, are generally not recommended for emeralds and can loosen the oils that fill surface fractures. Warm water and a soft brush is the safest approach for most colored stones.
Custom colored stone rings at acredo
Colored stone engagement rings are inherently custom projects — the stone you choose is unique, and the setting should be designed around it. At acredo in Denver, colored gemstones are sourced with full documentation, and the design process starts with finding a stone whose color, size, and character becomes the anchor for the entire ring.
If you're drawn to the idea of a colored center stone and want to explore what's available, consultations are available by appointment. Seeing the stones in person — the way the color shifts in different light, the depth and saturation — makes the decision considerably easier.