June 27, 2020 | Jewelry
Semi-precious gemstones: rarity, color, brilliance, transparency, durability, cut, optical effects and size are a few elements at play when determining the worth of a gem | Photo: Shutterstock

In the western world, diamond, ruby, emerald, and sapphire are the four gemstones deemed precious. The remaining gems are called semi-precious, but this title doesn't always reflect their value.

The ornamental use of jewelry and gemstones is deeply rooted in the history of humankind.

They developed personal, public, and spiritual meanings to men, gaining greater social importance as human civilizations became more evolved.

Gemstones seem to be particularly fascinating to us.

They hold religious, healing, reputation, political and wealth connotations, gaining the status of symbols in both ancient and modern societies.

Therefore, it is no surprise that in antiquity, the term precious was attributed to the rarest and most sought after gems at the time.

In the 19th century, the terms precious and semi-precious became widespread.

"Precious" labeled the shortlist of the most valued gems and "semi-precious" defined the remaining exemplars relevant to jewelry.

Currently, gemstones used in jewelry that are not diamond, ruby, emerald, or sapphire are generally called semi-precious, so the list of minerals under this classification is rather extensive.

Tiffany & Co. Blue Book 2019: a necklace with over 36-carat sapphires, blue cuprian, tourmaline, blue tourmaline, aquamarines and diamonds in platinum | Photo: Tiffany & Co.

Precious or Semi-Precious: What Is the Difference?

As ingrained in the collective awareness as they may be, the labels "precious" and "semi-precious" can be very deceiving.

They aren't scientifically based nor reflect the grade or quality of a gem.

Emerald (precious) and aquamarine (semi-precious), for example, are both varieties of beryl.

Several factors define the value of a gemstone.

Rarity, color, brilliance, transparency, durability, cut, optical effects and size are a few elements at play when determining the worth of a gem.

Some specimens called semi-precious are rarer and more valuable than the four precious gems.

Jade, opal, and pearl, for example, are often considered precious.

Amethyst was also a precious stone in the past until large deposits were found in Brazil and other locations.

Aside from rarity, size and quality also increase the price of a semi-precious gemstone, making it more expensive than some low-quality precious specimens.

The two labels are disregarded by experts and mostly used in the industry to highlight the four more popular rare gems in higher demand.

The correct designation for all jewelry grade minerals is "gem."

Pearl: the world's oldest gem is rare and highly valuable | Photo: Shutterstock

Semi-Precious Gems in Jewelry

The list of so-called semi-precious gemstones used in jewelry is long and full of wonder.

All gems are precious, each holding unique beauty and character.

Agate, alexandrite, amethyst, ametrine, aquamarine, cat's eye, citrine, garnet, lapis lazuli, moonstone, peridot, rose quartz, tourmaline, topaz, and turquoise are some examples of the most commonly used semi-precious minerals.

Aquamarine, the green-blue to blue variety of beryl, is an excellent jewelry gem.

Its name derives from the Latin words "aqua" and "marina," meaning "seawater." As the name suggests, aquamarine's delicate color exudes freshness and clarity.

Opal is a delicate stone used in jewelry for its incredible colors.

Precious opal displays play-of-color, an optical effect similar to a flash of bright, colorful light, and beautiful patterns.

These incredible minerals reach high market values, particularly black opals.

Pearl, although not a mineral, is considered the world's oldest gem. Today, the timeless natural pearl is very rare and, therefore, highly valuable.

The color-shifting alexandrite is an incredibly rare and prized gem.

It was first discovered in the Urals and became tsarist Russia's national gemstone.

These are only a few examples of extraordinary gems that fall under the semi-precious designation, without fitting in.

The more you look into the gemstones that appeal to you without considering the "precious" or "semi-precious" reputation, the more you will discover a fascinating world of beauty, novelty, and significance.

Paraiba tourmaline: a very rare gem has a superior average price than ruby and sapphire | Photo: David Morris

The Most Expensive Semi-Precious Gemstones

Since the term semi-precious doesn't accurately reflect the value of a gem, it is no surprise that some of these minerals reach amazingly high market values.

The very rare Paraiba tourmaline (up to $10,000 per carat), for example, has a superior average price than ruby and sapphire.

Black opal ($9,500 per carat) and alexandrite ($70,000 per carat) can match the emerald's average price.

Besides Paraiba tourmaline, black opal and alexandrite, fine quality exemplars of red beryl ($10,000 per carat), musgravite ($35,000 per carat), jadeite ($3 million per carat) and tanzanite ($1,200 per carat) feature among the most expensive gemstones in the world.

Semi-precious gemstones: amethyst, citrine, ruby, emerald and topaz are often used in high-end jewelry | Photo: Shutterstock

How to Choose

The first step is to look at what appeals to you.

Search liberally through the vast array of gemstone families and find the ones that better suit your taste.

Once your eyes are set on a particular mineral, look for information. Learn more about wearability, quality, availability, price, reliable sellers, etc.

Even more available gems possess excellent characteristics that shouldn't be overlooked - amethyst, topaz or turquoise are three great examples.

The preciousness of a gem resides in the eyes of the beholder, so dive into the world of gemstones with an open heart and find the one that is truly special to you.