Colored Gemstones

Watch Dr. Lori reveal how you can tell a more valuable gemstone simply by looking at the color of the stone.

Two rings with colored gemstones

by Dr. Lori Verderame

Identifying and Evaluating Colored Gemstones

Colored gemstones are always a welcomed gift and a very fine collectible. If your gemstone has no inclusions or visible imperfections, then that gemstone is worth more than one with such inclusions or imperfections. The most important thing to remember about colored gemstones is to evaluate them based on their individuality and the special properties which demonstrate how they develop in nature. Costume jewelry tries to simulate colored gemstones by using synthetic materials that look like the real thing.

Some gemstones have different qualities and attributes from others. Sure, the number of inclusions found in a colored gemstone will make an impact on how valuable that gemstone is but if you think of those imperfections as you would a birthmark on a child, you will start to understand that some inclusions are just part of the characteristics of a precious colored gemstone. Inclusions and imperfections speak to a gemstone’s individuality and special one-of-a-kind qualities. For instance, while emeralds regularly form in nature with visible inclusions, this is not a negative trait of emeralds but rather just one of the things that set emeralds, a stone native to Colombia, apart in the market.

Carats and Colors


Carat weight is the standard unit of weight for gemstones used by jewelers and gemologists. The ruby–also known as the red sapphire–rarely develops in nature in a size that is larger than one carat in weight. This is the reason why a ruby that is larger than one carat will cost you big bucks. They are rare and expensive.

Color is one of the most important aspects when identifying and evaluating colored gemstones. How clear a colored gemstone is will impact its value and spark interest with gemstone collectors. Those colored gemstones with a medium to dark tone hold good contrast and often command higher prices, depending on the type of stone.

The Mohs hardness scale measures a stone’s hardness. Some stones are very hard like garnets which have a hardness of 7.0 on the Mohs scale. Garnets develop in nature at places all over the world including Africa, Europe, and North America. Named for their similarity to the color of pomegranates, garnets were very popular in the early 1900s. They replaced jet and onyx that was all the rage in the late 1800s during the Victorian era. By the turn of the century, tastes changed toward the deep red color of the garnet. Garnets form in many colors including the commonly known dark red color as well as the lesser known colors for garnets such as orange, yellow, and even green.

Gemstones in History

In ancient times, people believed that gemstones had mystical powers. Roman emperor Nero used sliced emeralds to shade his eyes while watching gladiator events. These emeralds were the first lenses for sunglasses.

Amethyst, the purple stone that is closely aligned with quartz, was connected to the Greek god of wine, Dionysus.

Colored gemstone Tips

Opals, either white or fire, are rather soft stones when compared to other colored gemstones. They should not be exposed to excessive cleaning, water or prolonged periods in intense heat or severe cold. Amethysts may fade if exposed to prolonged periods of bright light. Garnets are very hard colored gemstones and will stand up well to everyday wear. They are more durable than many other colored gemstones.

What to Look For

Size or carat weight is important to establishing value for your colored gemstone. Color of your gemstone will impact value. Medium toned or dark toned colored gemstones give off a spectacular look when these colored gemstones are set in precious metals within jewelry pieces like rings, bracelets, pendants, etc. The color of a particular gemstone depends on the special, individual attributes of that gemstone.

Collectors should store each colored gemstone piece of jewelry separately to avoid scratching or damage. Store gemstone jewelry in a soft cloth bag, jewelry box with separated compartments, or a padded box. If you want to learn more about choosing the best colored gemstones, watch me explain gemstones in this video.

Values for Antique colored gemstones

There is a big difference between the value for an antique colored gemstone and the value for a contemporary colored gemstone. Be careful to learn the difference between a synthetic colored gemstone and one that formed naturally. Values for colored gemstones will be determined by many factors including but not limited to the quality of the stone, carat weight, inclusions, condition, traits of the jewelry setting in which the stone resides, and many other elements. Colored gemstones can sell for a few hundred dollars well into the six figure range. Antique colored gemstones have a very active and impressive collecting market.

Get an online appraisal of your piece of colored gemstone jewelry from Dr. Lori