Onyx Value, Price, and Jewelry Information
For millennia, artisans have carved intricate cameos from black-and-white onyx. Solid black onyxes, faceted or cabbed, are also popular jewelry…
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Identifying Jade Treatments
Jade is one of the most popular and expensive gemstones. It can also receive many enhancements. Learn about jade treatments and how to identify…
How to Build Pocket Crossed Filters for Gemstone Testing
The crossed filters technique allows gemologists to detect chromium in gems. Learn how to build a portable device for conducting this useful ID…
Peridot Buying Guide
Our peridot buying guide can help you learn how these gems are graded, what to avoid, and how to identify a high quality stone or a bargain in the rough.…
Benitoite Value, Price, and Jewelry Information
With dispersion higher than diamond and sapphire-blue body color, benitoite is one of the most attractive of all rare gems. Gem-quality crystals…
Helping Clients with Inherited Gemstones and Jewelry
Gem dealers are often their clients’ most trusted advisers on gem matters. Learn how to help your clients with inherited gemstones and jewelry.…
An Introduction to Gem Identification
Gem identification is part detective work, part art. Learn how gemologists can distinguish gem species and determine whether a stone is natural…
What are Lab-Grown Sapphires?
Learn how lab grown sapphires are made and how gemologists can distinguish natural from synthetic sapphires.
Covellite Value, Price, and Jewelry Information
Although covellite has attractive blue colors and shows iridescence, this rare mineral is difficult to cut. You can scratch it with a fingernail!…
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January Birthstone
Although many associate January's birthstone, garnet, with the color red, they can come in a variety of colors including red, yellow, orange, green and even blue.
February Birthstone
Thanks to its beauty and relative abundance, the February birthstone, amethyst, is used in all types of jewelry: from the mass market to the finest custom couture pieces.
March Birthstone
The March birthstone is aquamarine. Famed for millennia for its pure and even blue or blue-green color, potentially large size, and sparkling clarity, the aquamarine has been a valued gem to many cultures. Aquamarine is a variety of the gem species beryl, making it a close cousin of emerald.
April Birthstone
April's birthstone is diamond. The vast majority of diamonds are transparent, colorless, and show an extraordinary display of well-defined white and multi-colored flashes. Rarely, diamonds also occur in a rainbow of exciting body colors.
May Birthstone
May's birthstone is emerald, a rich green variety of the diverse beryl gem group which must exhibit a dark enough tone and saturation to be called by that name.
June Birthstone
June's birthstone is the pearl. Pearls can only be grown by a very small percentage of mollusk species which may live in either saltwater or freshwater environments. Each species produces a distinctive-looking pearl that is characterized by a specific range of colors and sizes.
July Birthstone
This vibrant red gemstone is the July birthstone and is closely associated with love, passion, and romance. While there are affordable options to be found, the largest and most beautifully colored rubies can be very expensive; the best rubies may be sold for the highest cost-per-carat costs of any colored gemstone.
August Birthstone
Peridot is the August birthstone. It is also sometimes called the “evening emerald” because of its unique capacity to sparkle under natural or artificial light. However, it should not be confused with emerald because peridot has its own distinct characteristics setting it apart from other gemstones.
September Birthstone
The September birthstone is sapphire. Sapphires are members of the gem species corundum. Depending on the exact chemistry of individual stones, sapphires may present a whole spectrum of colors with the exception of red. This is because red sapphires are put into their own category and called rubies.
October Birthstone
Pink tourmaline is the modern October birthstone, loved for its breathtaking beauty and awe-inspiring variations of the color pink.
November Birthstone
The most common birthstone for November is yellow topaz however citrine, another lovely yellow gemstone, has been rising in popularity as an alternative and is much easier to purchase.
December Birthstone
Blue zircon is known a modern December birthstones alongside blue topaz and tanzanite. The more traditional December birthstones are lapis lazuli and turquoise.
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