Jewelry > The Modern Precious Stones List

The Modern Precious Stones List

What are the names of precious stones? What makes them different from semi-precious stones? How do we go about identifying precious from the semi-precious? Exactly how long is the list of precious stones in the world? The precious stone names are fewer than you think. Here we explore the different types of precious stones, their names and pictures, and see how small the precious stones list has in fact gone down.

Cut Diamonds
Diamonds, the most popular precious stone
Source: Washington Diamonds/Inbal-Tania Studio via Wikimedia Commons

What are precious stones?

Precious stones are just that — precious. The catch is, how precious do stones have to be to be actually called precious stones? The word gemstones, or gems, applies to precious and semi-precious stones alike. What makes some gemstones precious stones, and others only semi-precious?

There are 3 qualities that characterize the precious stones of today: (1) beauty, that is, translucency and brilliance, (2) hardness, and (3) rarity. Two of these qualities, however, have not always been permanent. Tiger’s eye used to be a precious stone, even though the gemstone is, not translucent, but opaque. The tiger’s eye winning advantage was that the gemstone was extremely rare, at least it used be. Like tiger’s eye, amethyst was once a precious stone, until a huge deposit of the gemstone was found in Brazil and obliterated the gem’s fame for rarity. Their huge supply having been discovered, both tiger’s eye and amethyst plummeted in value and were consequently reduced to semi-precious stones.

Beauty is relative, they say. The saying is definitely true when it comes to gemstones. In fact, if we go through every one of them in history, the list of precious stones would probably be endless; since humanity’s appreciation of the gemstones goes right into prehistory. Fast forward, however, exactly how many are there in today’s precious stones list?

The Names of Precious Stones

The most certain figure would be 4. There are only four gemstones universally considered to be in the modern day’s list of precious stones. These four come from only three mineral groups, namely, corundum, beryl and diamond. Does it make you wonder how 4 precious stones consist of only 3 minerals? Let’s tackle each member of the contemporary precious stones list.

Diamonds set on a ring
Source: TQ Diamonds via Wikimedia Commons

1 Diamond

Diamonds are a girl’s bestfriend.

— song by Marilyn Monroe.

Diamonds are easily the most popular of precious stones, though not necessarily the most valuable. Not only is diamond the hardest gemstone on earth (10 out of 10 in the Mohs scale), the refractive index of the precious stone is a dazzling 2.418, which explains how the precious stone is so bright and brilliant — the gemstone keeps light within its translucent crystal about 2 ½ times longer.

While diamonds are commonly thought to be white, the precious stone occurs in practically all colors of the rainbow. In fact, except for the yellowish and brown varieties, fancy colored diamonds are even more expensive than white diamonds. Red diamond is the most expensive gemstone in the world. However, it does not follow that all colors of the mineral a precious stone belongs to are precious stones as well, as one of the next in the list would prove. See —

Ruby the red precious stone
Source: Humanfeather via Wikimedia Commons

2 Ruby

Ruby is a red precious stone that comes from the mineral group corundum, which is second only to diamond in hardness (9 out of 10 in the Mohs scale). An extremely rare gem, the red gemstone is more expensive than white diamond, and is the second most valuable precious stone in the world next to red diamond.

The color of ruby is caused mainly by the intrusion of chromium in the otherwise colorless mineral. The intensity of this red color is the most powerful determinant of ruby’s value. Accordingly, the most valuable of the precious stone are those whose color is a bright blood-red, also known as pigeon’s blood. On the other hand, a light red or pinkish piece of the precious stone is deemed inferior in quality. In fact, a pink ruby may not even be called ruby at all. What is it called?

A magnificent blue sapphire ring
Source: Stanislav Doronenko via Wikimedia Commons

3 Sapphire

While sapphire is most popular, and most valuable, in its deep blue variety, the precious stone occurs in all colors except red, with which the gemstone would be called ruby. Corundum that is even a shade less red than ruby is automatically called sapphire — pink sapphire. Like blue sapphire, the orange variety of sapphire named padparadscha also fetches a high price, as do black and blue star sapphires, or those that exhibit a star-like pattern when reflecting light.

Emerald on a ring
gemteck1, CC BY 2.0, via flickr

4 Emerald

Earlier I said, it does not follow that all colors of the mineral a precious stone belongs to are precious stones as well. This is particularly true with emerald. The reason possibly comes down to the name, the branding. Emerald is the green variety of the mineral called beryl. Any other variety of beryl is not called emerald. Light blue beryl is called aquamarine, the yellow beryl named heliodor, and the pink morganite. Since none of these varieties of beryl are branded as emerald, none of the beryl varieties enjoys the same status as their green cousin and gets called precious stone — not even the rarest of beryl, the red beryl, which is more expensive than emerald. Only emerald is among the names of precious stones. It is plausible that the best way to bring the other types of beryl into the precious stones list is to brand all of them as emerald — blue emerald, red emerald, yellow emerald, and so on — as is the case with sapphire.

Then again, the value of emerald lies above all in its color, the verdant green of the precious stone, to the point that emerald became the synonym of green. Even though the precious stone is usually fraught with surface fissures and its toughness compromised by numerous internal inclusions, emerald remains on the precious stones list for its color. The green gemstone is simply oiled to keep its fissures and inclusions from showing: a practice that has been widely accepted in the gem trade.

A blue opal set on a ring

Opal and Pearl?

If the precious stones list expands to 6 gemstones, the additional two gemstones would likely be opal and pearl. Both stones have been consistently popular and expensive up to the present era, and both display a play of colors that cannot be artificially imitated, hence their dependable value.

A white pearl necklace
Source: Emi Yañez , CC BY 2.0, via flickr

Precious opal is a gemstone that exhibits a brilliant play of colors against a certain body tone, which can be white, black or blue. The white opal, the most common of opal, can fetch a price of up to $2,000 a carat, while the rarest opal, the black opal, can be worth $8,000 per carat, more expensive than sapphire. Indeed, precious opals can be really very precious.

Like opal, the color of pearl is hardly a single shade, but a mix of different colors, often displaying a rainbow-like sheen. Black pearl is quite an expensive variety of pearl, but the most valuable is the rarest white pearl, the South Sea pearl. The value of pearls in general, however, is steadily being diminished by the growing supply of cultured pearls.

Aquamarine, the blue cousin of emerald

Past Precious Stone Names

Except for the four gemstones in the present list, precious stones come and go. Aquamarine, peridot and cymophane (cat’s eye) held their place in the list of precious stones up to the last century. Tiger’s eye and amethyst only fell off the precious stones list in the 19th century. In fact it was only with the downfall of amethyst that the term semi-precious stone was invented to mean a stone of less commercial value than a precious stone. Before this era, gemstones were practically all precious stones.

Indeed, tourmaline, alexandrite and garnet were among the names of precious stones, and rightly so, since these gemstones can even be more expensive than emerald or sapphires. In antiquity, topaz, zircon and moonstone were also in the precious stones list, as were opaque gemstones like turquoise, carnelian, agate, onyx, sardonyx, jasper and bloodstone.

Although amethyst ceased to be a precious stone, the gemstone is still highly revered, popularly representing the color violet of the stones.

Can the list of precious stones change?

The existence of new minerals is continually revealed to human knowledge, and new gemstones are found that can surpass the value of today’s four precious stones. For instance, grandidierite, discovered in 1902, is more valuable than ruby, diamond or emerald. Musgravite, discovered in 1967, is more pricey than sapphire. Others like benitoite, poudretteite, taaffeite and jeremejevite can well compete with at least a few sapphire varieties too. Can their actual value count these newfound gemstones among the different types of precious stones?

Unfortunately, no. But in here comes the irrelevance of the term precious stones in modern gemology.

Tiger eye was one highly valuable precious stone up to the 19th century.

Irrelevance of the Precious Stones List

The term precious stone is now largely irrelevant in the gemstone trade, not least because the use of the word precious stone falsely or inaccurately represent some gemstones to be more precious than others. For example, green jadeite can be more expensive than each of the four precious stones, and yet jade is always categorized as a semi-precious stone. Hence, the distinction between precious and semi-precious is steadily being abandoned. The paramount distinction now is on the jewelry itself.

Fine Jewelry vs. Fashion Jewelry

Today, from the question of whether a gemstone is precious stone or semi-precious, the paramount distinction has shifted to the jewelry itself: whether the jewelry is fine jewelry or fashion jewelry. Semi-precious stones are the most likely to come with a fashion jewelry, but are not precluded from being set in fine jewelry. There’s no stopping a jeweler from setting semi-precious stones in fine jewelry, be it in gold, sterling silver or platinum; neither is the customer unlikely to buy fine jewelry set with semi-precious stones, especially when the gemstone is his birthstone. Hence, while the four gemstones in the precious stones list enjoy immense popularity over other gemstones, semi-precious stones can be very valuable too, making the distinction between precious and semi-precious far less important.