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Barite Value, Price, and Jewelry Information

Massive white barite (also called known as baryte) looks like marble and could be used for decorative purposes. In spite of the abundance of good…

Faceting Machine Features: A Beginner’s Guide

Before investing in an expensive piece of equipment, learn how to examine these gem faceting machine features, so you can get the best tool for your…

Ten Gemstones Rarer than Diamond

If you’re looking for something unique for your next jewelry purchase, check out these ten gemstones rarer than diamond. How many have you heard…

Gemstone Polishing Laps and Techniques

No single gemstone polishing method will work for all people or all stones. Our guide will help you choose laps and techniques that work for you.…

Anorthite Value, Price, and Jewelry Information

The rarest plagioclase feldspar, anorthite is very rarely faceted.

Lapidary Tips for Polishing Girdles

What are the best techniques and tools for polishing girdles? Learn how to complete your faceted gems quickly and easily and avoid common errors.…

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Gem Price Guide

The world's best online resource for gemstone appraisal

Over 15 years, we have assembled detailed pricing and value information for appraising over 70 different gemstones. The values in our guide come from a variety of sources including primary and secondary gemstone dealers, jewelers, miners, and wholesale suppliers of commonly traded gemstones.

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Gemstone Encyclopedia

Our Gemstone Encyclopedia has information on over 300 gemstones, from traditional and popular jewelry standards to collector’s stones that rarely appear for sale. Each entry has photos and detailed information about the gem’s properties. Entries for jewelry stones also have price guidelines and discussions of their most important value factors.

Emerald

Emerald has been synonymous with the color green since ancient times. A fine emerald is a truly breathtaking sight, and this member of the beryl family deserves its placement among the traditional “Big Four” gems along with diamond, ruby, and sapphire.

Onyx

For millennia, artisans have carved intricate cameos from black-and-white onyx. Solid black onyxes, faceted or cabbed, are also popular jewelry stones.

Sapphire

Few gems have held our attention over millennia as well as sapphire. The pure blue colors and excellent durability of this gem-quality member of the corundum family make for an exceptional gemstone. However, not all sapphires are blue. The September birthstone comes in every color of the rainbow (except red).

Moissanite

When it comes to engagement ring stones, there’s a lot to consider. In the moissanite vs diamond debate, we’ll look at three main factors: beauty, durability, and price.

Hematite

Hematite has a long history of use as a pigment. As a gemstone, this material is often carved but very rarely faceted. Despite its association with blood and the color red, hematite’s color can range from black and metallic gray to brownish red in thin slivers or crystals.