Cut: Refers to the geometric shape and proportions of a gemstone. A gemstone’s cut is what most directly affects its sparkle or brilliance.

Facet: A flat cut on the surface of a gemstone.

Fire: Flashes of rainbow colors. Also called “dispersion.”

Hardness: Resistance to scratching. The higher the number, the more resistant.

Hue: Another word for color.

Luster: The shininess of a jewel.

Opaque: The opposite of transparent. Light cannot pass through an opaque gemstone, therefore they do not have any sparkle or fire.

Saturation: This term refers to how pure or deep a gemstone’s color is. Some gemstones, like aquamarine, have a naturally low saturation (very light blue) while other gemstones, like amethysts, can have very high saturation (rich, dark purple).

Sparkle: The white light leaving a jewel, traveling upward, which is visible to the eye. Sparkle is often referred to as “brilliance.”

Toughness: Resistance to breakage.

Gemstone Shapes & Cuts
These are the common shapes or cuts for gemstones, each lending a different look and allure.

Baguette: Baguette means “stick” or “rod” in French, which makes it a very appropriate name for this gemstone shape. Diamond baguettes are often used as accent stones to flank a primary stone.

Brilliant: Any gemstone cut with 58 facets, which produces the maximum possible sparkle. A brilliant cut can have several shapes, including round, oval, pear, radiant and heart.

Cabochon: This shape features a rounded, perfectly smooth surface instead of facets. It is the oldest gemstone shape and is commonly used with opaque stones such as opal, jade and turquoise.

Cushion: A very popular style for most of the 19th century, cushion shapes are slightly domed with rounded corners that make the stone look like a pillow. In fact, this shape is often referred to as a “pillow cut.” It looks particularly beautiful in candlelight.

Emerald: With its long, steep facets, emerald cuts tend to flash rather than sparkle.

Fancy: Technically, this term refers to any type of gemstone that isn’t round, but many jewelers reserve it to describe the more exotic gemstone shapes such as marquise, heart, pear and trillion.

Heart: Often described as a custom cut, heart-shaped gemstones are very popular for pendants.

Marquise: According to legend, this shape was commissioned by King Louis XV to resemble the smile of his mistress, Marquise de Pompadour. Ideal marquise cuts have a length to width ratio of 2:1.

Oval: Similar to the round shape, oval gemstones produce a high amount of sparkle and fire.

Pear: This is a classic teardrop shape that is ideal for earrings and pendants.

Princess: This a relatively new shape that combines the sharp, flat edges of an emerald shape with numerous small facets, which produce both sparkle and fire.

Radiant: This shape is similar to emerald, but it adds extra facets on the edges and corners to increase the gemstone’s sparkle.

Round: This classic shape produces maximum sparkle and fire, making it an ideal shape for diamonds.

Tapered Baguette: A tapered baguette is a baguette shape with one end that is narrower than the other.

Trillion: A very striking, usually three-sided shape, trillion gemstones (especially diamonds) are celebrated for the intense fire they produce.

The Mohs Scale
The most common measure of a gemstone's degree of hardness is based on the Mohs Scale. Devised by German geologist Friedrich Mohs in 1812, the Mohs Scale grades minerals on a comparative scale from 1 (very soft) to 10 (very hard).

Hardness is generally associated with durability and the ability to resist breakage. When referring to gemstones, however, hardness more accurately means the stone's ability to resist abrasion. What the scale means is that a mineral of a given hardness rating will scratch other minerals of the same rating, as well as any minerals of a lower hardness rating. For example, rubies and sapphires, which are composed of the mineral corundum and have a Mohs rating of 9, will scratch each other, as well as topaz (rating 8) and quartz (rating 7). But they will not scratch diamonds, which are rated 10 and considered the hardest substance.

The numeric values assigned to each interval of hardness are not equal. Some stones are disproportionately harder than others. Because Mohs Scale wasn't made for exact precision, it uses half numbers for in-between hardness ratings.

Garnet:

Garnet comes in a vast rainbow of naturally exquisite hues, occurring in every color except blue. It is the family of minerals that displays the greatest variety of colors than any other mineral. The eight major types of garnets include almandine, pyrope, demantoid, grossularite, tsavorite, hessonite, rhodolite and spessartite.

Named after the ancient gemstone city of Alabanda in Asia Minor, the most common type of garnet is almandine (also called almandite). It is a dark red to brownish red stone that is only slightly different from the chemical structure of its sister stone, called pyrope. While nature only grows pyropes in small sizes, it allows for almandine crystals to form in larger dimensions.

Pyrope is a high-quality garnet that can be purplish red, blood red, orange-red or crimson. It is often called the Bohemian garnet since its fierce and often slightly bronze color was highly popular in the 18th and 19th centuries when it came from the north-eastern part of the former Kingdom of Bohemia. In Europe during the Victorian times, pyrope garnets frequently decorated jewelry with many of these small stones tightly arranged along each other like the seeds of a pomegranate. In fact, the name “garnet” most likely was derived from the pomegranate, a fruit whose deep, red-purple color resembles some varieties of the gem. Many ancient pieces of garnet jewelry are also studded with the tiny red gems.

Demantoid is a rich green variety of garnet primarily found in the Ural Mountains of Russia. Russia’s leading court jeweler, Carl Fabergé, loved this brilliant garnet more than any other stone and used it in many of his creations that were lavishly adorned by the Tsars of Russia. Today, demantoid is appearing more often in the gemstone market because of new finds in Namibia. However, these particular garnets from Namibia lack "horsetail-inclusions,” the fine bushy-shaped inclusions that are characteristic of the sought-after Russian demantoids. The gem is quite rare and can cost several thousand dollars per carat depending on size and quality. The larger, brighter demantoids are exceedingly scarce and have been known to show exceptional brilliance, even higher than diamonds.

Grossularite, available in pinks, browns, greens and yellows, is especially cherished because of its many in-between shades and earth colors. In the last year of the 20th century, large grossularite occurrences were discovered in Mali. Charming because of their high brilliance, the Mali garnets make even the brown color attractive and vivid.

Tsavorite is the trade name for a fine green grossularite. It ranges from vivid light green to velvety deep green and, like all other garnets, features a strikingly high brilliance. Tsavorite was discovered in 1967 by British geologist Campbell R. Bridges, and was re-named by Tiffany’s in New York after its occurrence near the famous game park Tsavo-National Park. Mined in Tanzania and Kenya, this particular stone is quite rare and can cost several thousand dollars per carat depending on size and quality. Larger tsavorites are exceedingly scarce.

Hessonite is the variety name for a fine orange, cinnamon brown or pinkish variety of grossularite. It most commonly occurs in golds, oranges and browns.

Rhodolite is a pyrope-almandine garnet that features a velvety red color with a fine purple or raspberry colored undertone. One of the most popular varieties, it is mined in East Africa, India and Sri Lanka and was originally discovered in the United States.

Spessartite garnet can be red or blackish brown, but is most commonly available in golds, oranges and warmer browns. Originally named after its occurrence in the German Spessart Mountains, there was a surprising discovery of the bright orange-red stone in Nigeria and Namibia. Until then, spessartites had existed as mere collector’s items or rarities and were hardly ever used for jewelry because they were so rare. But the new location discovery changed the world of jewelry gemstones and spessartites made their way into jewelry fashion. The most popular type of spessartite is the mandarin garnet, a gem that features a bright orange hue.

Traditionally given as 2nd wedding anniversary gifts, garnets are celebrated as January’s birthstone. They are found all over the world, including Africa, Australia, Eastern Europe, the Middle East, North America, South and Central America, and Southeast Asia. The garnet ranges from 7.0-7.5 on the Mohs Scale and has been given many different names throughout the gemstone trade, including Arizona Ruby, Arizona Spinel, Montana Ruby or New Mexico Ruby. The stone features a high refraction of light that creates an amazing brilliance and luminosity. In fact, Noah used a garnet lantern to illuminate the darkness and navigate the Ark through 40 days and nights of torrential rain.

Throughout history, garnets have been widely known and prized for their rich hues and supposed mystical properties. Adored by the ancient Egyptian goddess Isis, the gem symbolized faith, truth and friendship and was a favorite of Egyptian jewelry artisans. Garnets were taken into the tombs with the dead as payment to the gods for safe passage through the nether world. It is said that King Solomon wore a large red garnet along with eleven other magical gems in his breastplate (representing the 12 steps of Jacob's Ladder) to help him win battles. Nineteenth-century Asiatic warriors even used the hard stones as bullets. In the 13th century, medieval travelers wore garnets as popular talismans and protective stones, many of which were carved with lions. The gems were thought to repel evil spirits, bad dreams and people with evil intent.

Today, garnets are thought to have protective powers and can be carried by travelers to protect against accidents. The stone is said to light up the night and protect its owner from nightmares. It is also believed to strengthen the body and mind by sparking creativity, dispelling anger and curing depression. People may use the stone to increase the power of their energy fields and gather good vibes. Current superstitions say that the stone symbolizes loyalty and can be exchanged between friends to symbolize affection and ensure they meet again. When used as a healing stone, it is said to relieve skin inflammations and regulate blood flow.