GEMSTONE COLOR CHART
Color is undoubtedly the most important criterion for evaluating and selecting gems. But because gemstone jewelry comes in an assortment of shades, color grading can be very complex. The three criteria experts look at are hue, tone, and saturation, which, combined, result in the colors we see. Lighting is another essential factor since gem coloring and brilliance can vary depending on the light source.
Major Factors That Determine The Color of a Gemstone
Hue refers to gemstone’s base color. It is usually made up of only one color, but it can also consist of a combination of hues, resulting in additional colors for precious stones, such as orange-red, yellow-orange, yellow-green, yellow-brown, green-blue, or violet-blue. The Gemological Institute of America (GIA) has developed a list of 31 hues for describing gemstones, consisting of 7 base hues and 24 combination hues. Gems with a single pure and vibrant hue tend to be the most highly valued.
Tone describes the relative lightness or darkness of a gem’s color. A pink gemstone, for instance, might be categorized as “light pink” or “medium pink”, while a green-colored gem can range from lime to deep forest green. The GIA tone scale has a total of 11 points, going from colorless to black.
Saturation is the intensity or purity of a color. Gemstone color becomes less pure with lower saturation, and an additional gray or brown hue can be seen. Thus, the most desirable gem varieties are those that exhibit strong saturation and an even color throughout.
According to the GIA saturation scale, there are six degrees of saturation, ranging from grayish or brownish to vivid. As saturation decreases, a gem with cool hues can appear grayish, while a gem with warm hues can appear brownish.
Gemstones by color
Here is a list of gemstones according to color.
Blue Green / Blue Gemstones
Blue Sapphire, Blue Tourmaline, Blue Tanzanite, Iolite, Flourite, Aquamarine, Blue Opal, Blue Spinel, Turquoise, Lapis Lazuli, Blue Zircon, Chert (a type of dark blue microcrystalline rock).
Violet or Purple Gemstones
Amethyst, Purple Garnet, Topaz, Purple or Violet Sapphire, Iolite, Tanzanite, Purple Diamond, Purple Chalcedony, Purple Spinel, Purple Jade, Purple Fluorite, Purple Kunzite, Purple Tourmaline.
Rose Quartz, Star Ruby, Rhodonite, Rubellite, Pink Tourmaline, Pink Opal, Pink Fluorite, Kunzite, Morganite, Star Garnet, and Pink Spinel.
Orange Diamond, Orange Sapphire, Orange Zircon, Imperial Topaz, Oregon Sunstone, Spessartine Garnet, Mexican Fire Opal, Orange Spinel, Amber, Tourmaline, Tangerine Quartz.
Obsidian, Black Onyx, Tahitian Pearl, Black Opal, Black Diamond, Schorl Tourmaline.
White Gemstones or Colorless Gemstones
Colorless Diamonds, White Sapphire, White Topaz, White Agate, Pearls (Natural and Cultured Pearls), White Opal, Transparent Opal, White Jade, White Jasper, Rainbow Moonstone.
Whether it’s a colorless diamond or another white or colorless gem, these are the gems most often used for engagement rings, with diamond being the most popular choice.
Multicolor Gemstones & Colorful Gemstones
Multicolor Agate, Multicolor Ammolite, Multicolor Andalusite, Multicolor Black Opal, Multicolor Bloodstone (Heliotrope), Multicolor Cat’s Eye Opal, Multicolor Chocolate Opal, Multicolor Chrysocolla, Color-Change Diaspore, Color-Change Fluorite, Color Change Garnet, untreated Color Change Sapphires, Multicolor Coral, Multicolor Dendritic Agate, Multicolor Fire Agate, Rainbow fluorite, Multicolor Hawk’s Eye, Multicolor Labradorite, Multicolor Mystic Quartz, Multicolor Mystic Topaz, Rainbow Pyrite, Multicolor Rhodochrosite, Multicolor Ruby-Zoisite, Watermelon Tourmaline.
Frequently Asked Questions
Gemstones come in a myriad of colors, and a colored gemstone is an attractive addition to any jewelry collection. Gemstones can even be multicolored, such as Watermelon Tourmaline, which features a green edge and a pink center.
All precious gemstones are graded according to the 4Cs of gem quality, one of which is color. The more vivid the color, the higher the stone’s value.
Red gems are the most unusual gems. The renowned Pigeon’s Blood Ruby, which is a bright red hue tinged with purple, is exceptionally rare.
Emeralds are one of the most expensive colored stones. These radiant green gems, especially those with a greenish-blue hue, often turn out to be more expensive than a Diamond of the same quality. The most expensive of these green gems was the Rockefeller Emerald, which sold for a staggering $5.51 million in 2017.
Color clarity refers to the quality of a gemstone with regards to the appearance of surface defects (called “blemishes”) or internal inclusions (i.e., imperfections).
Rainbow Fluorite is regarded as the most colorful among all the other gemstones due to the variety of brilliant colors that are present in a single stone. These are also among the most popular minerals among gem and mineral collectors, next to Quartz.
The beautiful pastel pink Rose Quartz is said to be the classic stone of love, traditionally held to open the heart chakra and draw love (or romance) into the life of the wearer.
However, Rubies are also associated with love and come in a range of different shades, from deep reds to subtle pinks.
The Kashmir Sapphire, which is a stunning violet-blue gemstone, is the most highly prized variety of Blue Sapphire and, thus, the most expensive. This vivid blue stone is sometimes said to have a velvety texture and is often associated with royalty.
The Zircon gemstone comes in an assortment of colors, from yellow and green to red and reddish-brown. However, the most popular color for Zircon is ocean blue. Virtually all Blue Zircon is heat-treated to intensify its beautiful blue color.
Sapphires and Rubies belong to the mineral variety corundum. While Rubies are inherently red, Sapphires come in an array of colors (Sapphires that are any other color besides blue are known as Fancy Sapphires). The bright color of these gems is caused by various ions present in the mineral when the crystal is formed. Thus, you can find canary yellow and pink-orange corundum along with the more well-known colors of blue and red. Red colors result from the presence of chromium, while titanium and iron produce the intense blue color that Sapphire is renowned for.
Emeralds are prized for their radiant green color, which can range from greenish-blue to yellowish-green, depending on where the stones were mined. However, gems with blue tones are more highly valued than those with a yellow tint.
Rubies are exclusively red, but their hue can vary in terms of tone, saturation, and secondary colors. Thus, Rubies can have orange, purple, or pink undertones, ranging from hot magenta to bubblegum pink. Others may exhibit a warm raspberry tone more commonly associated with these colored stones.
The major factors that determine the color of a gemstone are hue, tone, and saturation.
Yes, color change gemstones do exist. These gems change color depending on their light source. For example, Alexandrite features green colors in the daylight and changes to a fine red ruby color under white or incandescent light.
Green is arguably the most common color in the gem world, but only because there are more varieties of green gemstones.
The 4 Cs of gemstones determine their quality. These factors are:
Peridot is a variety of the mineral olivine. It is among the few gemstones only found in one color, green. The brightness and hue of this colored stone depend on the amount of iron present in its structure. Thus, individual Peridot gems can feature yellow-green or canary yellow hues, olive green colors, or green tinged with brown. It can also sometimes have the appearance of yellow gold and was called the “gem of the sun” by ancient Egyptians.
Apatite is a brittle gem belonging to a group of phosphate minerals. It comes in a variety of colors, including green, brown, blue, yellow, pink, violet, and colorless. Specimens with excellent color and clarity are often cut as cabochon gemstones.
Topaz is naturally colorless, but gems containing trace element impurities can range from pale blue to golden-brown or yellow-orange. Topaz also becomes a deep blue, reddish-orange, pale green, pink or purple when treated with heat or radiation. A Sherry Red Topaz is an example of a stone that has been heat-treated. Imperial Topaz is the rarest form of this gem variety, which exhibits a golden-orange-to-pink hue. A lot of this variety comes from the Ouro Preto Region in Brazil.
The darkest gems that are used for jewelry are:
Black Opal tops the list of the most highly valued black stones. Surprisingly, Black Opals are not entirely black. Instead, they are characterized by an infinite display of colors against a dark background. The largest and most valuable Black Opal, known as “The Royal One”, weighs 306 carats and is valued at over $3 million.
There are purple gems, with the most popular being the Amethyst, Purple Sapphire, and the Khooni Neelam (a type of blue Sapphire).
Citrine is a gemstone belonging to the Quartz family. Its colors range from pale yellow to amber gold, although brown colors are also sometimes seen in lower-grade gems.