Diamonds may be a girl’s best friend, but sapphires are increasingly becoming a BFF to many brides and grooms. Here’s what you need to know about selecting a sapphire for an engagement ring, courtesy of

A rich and royal history

Stunning sapphires have been a highly prized gemstone throughout history, cherished for generations as a symbol for virtue, nobility, truth, holiness, wisdom and good fortune — and they’re becoming increasingly popular as unique and affordable engagement rings.

Sapphire engagement rings have a rich and royal history. In 1981, Princess Diana chose a sapphire engagement ring for her engagement to Prince Charles. Upon Diana’s death, the ring went to Prince Harry, while Prince William received a Cartier watch. But the two brothers had an agreement that whoever became engaged first would present the ring to their betrothed. William romantically proposed to Kate Middleton while they were on vacation in Kenya.

The royal engagement ring is a deep blue oval sapphire — estimated at 12 carats — encircled by 14 round diamonds set in 18K white gold. Middleton decided to have the engagement ring resized by the royal jewelers G. Collins & Sons to fit her finger better. She asked them to attach small platinum beads inside the bottom of the ring to make it a size I, one notch up from her own finger width.

More reasons to go with a sapphire

Sapphires come in a wide variety of colors, from vivid blues and pinks to yellow, green, orange, brown, red and clear.

Again, they’re generally more affordable than diamonds, which allows you to buy a larger sapphire on the same budget.

Sapphires are also super durable. They’re great for everyday wear with excellent durability and are nearly as hard as diamonds, which makes them very difficult to chip or break. They are also able to withstand heat, light, and chemicals making them ideal for everyday wear.

The Mohs Scale measures minerals specifically on their ability to withstand abrasions and scratching by other minerals. A diamond is rated 10 on the Mohs scale, while a sapphire is rated 9. This indicates that the sapphire has excellent hardness, so much so that the only other natural gemstone that could scratch a sapphire would be a diamond.

Also, sapphire engagement rings featuring vibrant sapphires alone have a distinct appeal, allowing the eye to be drawn toward the singular, sparkling gem.

Considering color, shape and size

When selecting the perfect sapphire, the most important factors to consider are color, shape, and size. While there are no standard measurements like the 4Cs for diamonds, deep blue is the most desired and valuable sapphire color.

Most people think sapphire stones only come in the color blue, but sapphires come in a wide variety of colors, each with a different meaning.

The saturation of the color is also a key indicator of the quality of a sapphire. Sapphires with an even coloring command a premium over lighter, less saturated sapphires or darker, inkier ones. In addition, make sure the sapphire you select has no inclusions, or tiny imperfections, visible to the eye.

When it comes to shape, the most popular choices for a sapphire center stone are usually oval, round, cushion, and emerald. The standard size for a round sapphire is 6mm — the equivalent of a .75 carat diamond. Oval sapphires are also an excellent choice. Kate Middleton’s engagement ring is crowned by a large, beautiful oval sapphire. Since sapphires do not have a standard guideline for an ideal cut, each sapphire must be custom cut to help the finished gem display the best color and brilliance.

The ring setting

Once you have decided on the color and shape, the next thing to consider is the ring’s setting. Most ring settings will be either yellow, white gold, or platinum. Although sapphires can be complemented by other colored gemstones, they look even more stunning when paired with accent diamonds, which sparkle next to the deep blue.