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Silk inclusions in sapphires are hard to detect. Learn to pick the best orientation and cut for these gems. You might end up with a prize star sapphire.…
Traditional diamond cut grading methods prepare gemologists for making evaluations with minimal time, tools, and references. This step-by-step…
Colemanite is an abundant mineral, and transparent material isn’t rare. However, gem cutters rarely facet these typically pale stones. Difficult…
How can you determine the gold karatage of an item and learn if it’s gold-filled or plated? This simple technique will do the trick.
Compare the prices and philosophies of gem faceting classes from around the world. Learn if there’s a local club or a faraway school that’s…
Our opal buying guide can help you learn how opals are graded, what to avoid, and how to identify a high quality stone or a bargain in the rough.
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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.
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.
For millennia, artisans have carved intricate cameos from black-and-white onyx
. Solid black onyxes, faceted or cabbed, are also popular jewelry stones.
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).
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.
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.
We’ve compiled information on average costs and sizes for different diamond cuts
and shapes at different carat weights. Learn how the different fancy cuts compare, and the pros and cons of different diamond cuts.
An olive to bottle-green natural glass, moldavite
is a rare material popular with collectors of unusual gems as well as those interested in its formation from a meteorite impact.
is the most common form of natural glass and occurs in many attractive varieties. Since prehistoric times, people have used this material to make jewelry and carvings as well as practical objects, like knives.