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Sapphire Sparkle Collection: Gemstones & Tools for Brilliance
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What Is A Sapphire?

Comprehensive guides that provide you with the information you need to select gemstones that you'll treasure forever.

What Is A Sapphire?

Sapphire Carat Weight and Size

The value of these highly desired precious stones is measured by weight and density. Gems vary in density, meaning that even if a diamond has the same carat weight as a sapphire, they are visually different sizes. Because sapphires tend to be heavier, a one carat sapphire is generally slightly smaller in size than a one carat diamond.

For ease of selection and setting, size is a more useful measurement than carat. We list gemstone sizes in millimeters (mm). Our standard size for a round sapphire is 6 mm, which is approximately one carat.

Sapphires of different shapes compare differently in carat weight and mm size. So, depending on the shape, what size is a one carat sapphire?

  • Round and heart shaped sapphires: 6.5 mm
  • Oval and pear shaped sapphires: 7.7 x 5.7 mm
  • Emerald and radiant shaped sapphires: 7.4 mm
  • Princess, cushion, and asscher shaped sapphires: 5.5 mm
  • Marquise shaped sapphires: 10.5 mm

Sapphire Cut

A personalized cut is crucial to bringing out the unique personality of a sapphire. Unlike diamonds, there are no standard "ideal" cuts for sapphires, as each individual sapphire crystal must be custom cut to help the finished gem display the best color and brilliance.

Color can display in different proportions throughout a rough natural sapphire. Cutters must consider how best to orient the stone and cut facets into the stone to best reflect the sapphire's exceptional color through the table or the top of the stone. Thus, a well-cut sapphire displays the color of the gemstone to its best ability while still enhancing luster and brilliance.

Often, gemstones exhibiting a lighter tone of color will be cut deeper to add dimension and intensity to the color reflected through the table. A sapphire of a very dark color will likely be cut shallower to allow more light to reflect within the gemstone, softening and brightening the color. Both methods enhance a sapphire's unique beauty.

Regardless of the shape of the sapphire, the edges should be symmetrical and even. The facets on the top of the gem, the "crown," should be even in size, shape, and location. The largest facet on the top of the crown, known as the table, will be symmetrical in shape and well-centered. When the sapphire is rocked and tilted, it should produce bright color flashes as it moves, with no dull spots present.

Since sapphires come in such a broad variety of colors, each with its own unique properties, there are no specific proportion requirements. Because of this lack of standardization, sapphire cuts are generally not graded by gem laboratories. Instead, jewelers set their own standards for cut and focus on the color of a sapphire to determine quality.

Types Of Sapphire Cuts

A sapphire’s cut refers to the technique of transforming the rough stone into a faceted, brilliant, polished gemstone. Cutting facets, or flat surfaces, onto the stone gives sapphires their elegant radiance, and the size and number of facets in the cut distinguishes one sapphire cut from another.

Rare and expensive, cutters tend to shape sapphires into ovals or cushions to retain as much of the rough stone as possible. Round shapes, popular with diamonds, need much of the rough stone cut away to attain the round shape, making round shapes more expensive.

The unique shape and cut of a sapphire partner together to enhance the quality of both the color and the brilliance of sapphires. Sapphires come in a wide array of exquisite cuts ideal for engagement rings, pendants, bracelets, and any type of fine jewelry. Although the most popular gemstone cuts tend to be the round cut and princess cut, the best cut for sapphires is the one that suits your needs the best.

How Sapphire Shape Impacts Cut

The exceptional artistry of cutting facets into a rough stone takes careful consideration of the natural sapphire. The cutter examines each high-quality gemstone to determine how best to shape it and retain as much size and carat weight as possible while bringing out its brilliant color.

A natural sapphire forms a hexagonal crystalline structure. This structure allows sapphires to be cut in a variety of shapes and still maintain their durability. Cutters examine these rough sapphire crystals to determine the best finished shape. They consider the color zoning and the lightness and darkness throughout the crystal before determining the shape and selecting the type of facets. Facets come in two forms: brilliant and step. Brilliant facets maximize light reflected from the stone and step facets maximize the appearance of color.

The angle of the facets impacts how much a gem sparkles by reflecting light back to the eye. The ideal angle for facets differs with each sapphire. The facet cuts and angles must be even and symmetrical for brilliant, high-quality sparkle. Cutters examine each stone to determine the angle needed for the facets to give each sapphire its exceptional sparkle.

How Sapphire Color Impacts Cut

Sapphires commonly exhibit color zoning, areas of different colors in the stone. As is the case with shape, cutters examine the color zoning in the rough stone before cutting and determine how best to maximize the color by cutting. Cutters cut deeply if the stone is too light, and they cut more shallow if the sapphire is dark to bring more light through the stone.

Although color zoning is prevalent in sapphires, sapphires come in many colors, and each color has its own set of color challenges. Blue sapphires, for example, have angular zones of darker blue and lighter blue, while other types of sapphires have color concentrated at the surface. Cutters also consider pleochroism, different colors that reflect from different viewing positions. Regardless of the color challenges, cutters orient the stone so that the finished gem appears entirely one shade of blue.

The goal of every high-quality cut is to finish with a sapphire that has even saturation, beautiful color reflecting through the table, and a brilliance of sparkle that makes it look alive.

Cutters also inspect the original sapphire for inclusions, material trapped inside the stone. While inclusions affect a sapphire’s clarity, inclusions can also cause white spots in a sapphire and cause color zoning. Cutters carefully cut away inclusions while cutting and shaping sapphires. To enhance the natural color of the stone, the location of the inclusions and how they affect the color will impact the cuts made. A finished sapphire should have an even color and a beautiful luster.

Although every sapphire still retains some inclusions, cutters mask the inclusions so they can’t be seen with the eye. Unlike diamonds that are magnified for examination, sapphires don’t undergo magnification for inclusions. Sapphires need only to be “eye-clean” to be considered worthy. The cleaner the sapphire, the better the quality.

The exceptional artistry applied to cut sapphires while taking their color challenges into account is notable. The quality of our sapphires remains high as we select stones with excellent hue, saturation, and tone, refined by expert cutters for the best natural beauty color of our gemstones.

Clarity in sapphires is viewed in a much different way than it is with diamonds. Sapphires form in an environment rich with trace minerals that can easily become trapped within the gemstone itself. Some of these might show themselves as small crystals or needle-like inclusions, so it is an accepted fact that all sapphires will have some clarity characteristics or "inclusions." Because of the depth of color that a sapphire possesses, clarity characteristics are often easily masked and unnoticeable. Sapphires with no inclusions easily viewable with the naked eye are deemed "eye-clean" and offer an excellent value. Brilliant Earth only selects eye-clean sapphires. We also offer very high clarity sapphires at a premium.