Gemstone Buying Guide
Gemstones come in a near‐infinite variety of shapes and colors. Ranging from popular stones such as rubies, sapphires, and emeralds to less common gems like chalcedony, and moonstone, gemstones show off nature's incredible ability to create beauty in so many different shapes and forms.
What is a gemstone?
In order to be classified as a gemstone, a piece must be comprised of a naturally occurring mineral or organic material and must possess beauty, rarity, a reasonable degree of durability, and value.
Materials as diverse as sapphire, coral, and opal are all considered gemstones.
What cuts and styles can you find gemstones in?
Gemstones are available in a large array of cuts, shapes, and styles thanks to the many creative lapidary artists. Traditional shapes include round, oval, pear, marquise, and emerald cuts. Colored gemstones can also be found in the versatile cabochon (rounded, non‐faceted shape) and fancy cuts (when gemstones are sculpted into other objects) which can offer incredible diversity and shapes that can fit countless looks.
Learn more about popular shapes of gemstones.
What colors do gemstones come in?
Oh goodness, where do we start? You can find gemstones in every color of the rainbow, plus all of the colors in between. From light pink morganite to fascinating topaz, you can truly find a gemstone for every look.
How do you evaluate the color of a gemstone?
There are three main factors that go into evaluating the color of a gemstone:
Hue
Hue is the basic color sensation: blue, red, green, etc. Hue can also refer to blends of colors like purplish red, violet blue, etc. In some gemstones, such as rubies and emeralds, having a true hue is considered most desirable. In other stones, however, a combination of colors‐‐like blue green in a tourmaline or violet blue in a tanzanite‐‐is considered ideal and will command a higher price.
Saturation
Saturation refers to the visual intensity of a color. Imagine putting drops of orange food coloring into a glass of water. With one drop, the water gets a slight orange tint, which we would call low intensity in the gemstone world. With 50 drops of food coloring in the glass, the water becomes obviously orange. We call this high intensity. The more saturated a colored gemstone is, the more valuable it is considered.
Tone
Tone is the degree of darkness or lightness of a color. For example, a blue sapphire may range from a very light blue color to a very dark blue. This would be a variation in tone. In general, the higher a gem's saturation, the darker its tone.
How is the value of gemstones determined?
The value of a specific gemstone comes from a combination of its color, clarity, cut, and rarity. Rarity typically refers to the prevalence of a stone itself‐‐how many places can a particular stone be found in the world, how difficult are they to mine, how many gems are found or extracted‐‐but can also refer to the relative rarity of a specific size or type of the specific gemstone. While clarity and cut do affect the overall value of a gem, color typically has the greatest impact on the quality. Generally, the purest and most vibrant color possible in any given colored gemstone is the rarest and most valuable.