Sondra Francis

If you are shopping for a large diamond, .75 carat or more, you should look for a loose stone, or...

Rubies and sapphires are the same mineral: corundum, with different trace minerals creating a wide variety of color. Rubies and...

You may never have heard of iolite. It isn't a household word, but it is an attractive indigo colored gemstone....

Ironically, chrysoberyl varieties include two of the world's most exotic and expensive gems, alexandrite and cat's-eye chrysoberyl, while yellow or...

Aquamarine was the talisman of the sailor for centuries, its colors resemble those of the sea and it has a...

Andalusite is an unusual stone. It shows flashes of several different earth tones in the same stone. Because of its...

Each gemstone species has unique properties; the informed buyer can save time when he knows what is feasible and what...

To simplify your pursuit of gemstone knowledge, the varieties discussed in this book will be described in the mineral species....

The treatment and enhancement of gemstones has existed for centuries. Some enhancements improve on nature slightly, are undetectable, and they...

The valuation of a gemstone is derived from the "FOUR C's": carat, color, clarity, and cut. Understanding all four of...

The most valuable gems come from crystallized minerals that have formed under heat and pressure deep inside the earth. The...

The beauty, color, and brilliance of each different gemstone variety is a result of its unique set of physical and...

Gemstones have been treasured by humankind since the beginnings of civilization. Every ancient civilization found practical and decorative purposes for...

This book is written as a guideline for the potential buyer of gemstones that are mined from the earth or...

This page contains the list of Gemstone Glossary from the book Gem Dealers' Secrets - Handbook for the Gem Buyer,...

At the time of Moses twelve gemstones comprised the Jewish High-Priest's Breastplate of Aaron; each stone represented one of the...

The first man-made gem materials dates back a few thousand years; early Romans made glass beads and gems. Since natural...

here are many minerals accepted as gem materials. Some gem materials are organic in origin rather than mineral, such as...

If you are looking at a tanzanite it is critical to view it under different lighting conditions. In daylight tanzanite...

Zircons were called "jacinth" or "hyacinth" in older writings. Zircons are exceptionally brilliant gemstones; the high zircon has the highest...

Turquoise has a long history as a gemstone. It was one of the favorites of the ancient Egyptians. Its name...

The most common tourmaline colors are greens and pinks. Yellow and violet tourmalines are relatively rare. Tourmaline that falls into...

Topaz is a gem that is very often eye clean, so stones with good clarity are available. The red color...

The most famous ruby in the world is actually a spinel! It is the "Prince Edward Ruby" which is the...

Quartz is generally divided into two groups: the transparent crystalline varieties and the translucent to opaque chalcedonies that are microcrystalline...

Pearls are organic gem materials form in a variety of mollusks when the mollusk covers an irritant with layers of...

Every opal is unique in appearance. Opals contain fireworks of every possible color dancing inside them. The flashes of color...

Cleopatra was reported to have a fine collection of emerald jewelry, but rumor has it that it was really peridot....

Lapis lazuli differs from other gem materials because it is a "rock" composed of several minerals rather than being a...

Jade is a confusing term since it is used to refer to two different gem materials. The two jades, jadeite...

Garnets are a group of related minerals which have slight variations in chemistry but a common cubic crystal structure. Many...

The feldspars are a group of related minerals which, as a group are the most abundant minerals in the earth's...