The families of gems

Welcome to the world of gemology! We will introduce you to the best-known families of gems. These notions are fundamental to the appraisal of your beautiful jewelry. Happy reading!

Diamond

To be brief, and to tell you what you may not already know, diamond is a mineral made entirely of carbon. Just like pencil lead, you may say! But what makes diamond rare are the extreme conditions in which it forms: more than 150 km below the Earth's surface, at a temperature of 1,500 degrees and under tremendous pressure. And even when all these conditions are met, less than 10% of the diamonds found are of sufficient quality to be used in jewelry!

To this day, diamond is the most sought-after gem and the hardest in the world (10 on the Mohs scale). A diamond is not necessarily white, either: it can be yellow, pink, blue… These colored diamonds reach record prices at auction. It is hard to give a price per carat for a diamond, as it varies so much with its characteristics: color, clarity, carat weight and quality of cut, commonly known as "the 4 Cs".

To have a jewel set with diamonds appraised or to sell it, we are here to help: contact us.

Corundum

Unlike diamond, corundums are minerals made mainly of aluminum oxide. Among the best known, I call to the stand sapphire (blue) and ruby (red, owing to the presence of chromium)! Corundums of other colors are known as fancy sapphires. The most sought-after rubies are called "pigeon's blood", after the very particular shade of red that characterizes them. One of them sold at auction at Sotheby's for more than 30 million dollars.

Beryl

Beryl belongs to the silicate family. The term may not mean much to you, but you certainly know it. It is the gem that seers once used to read the future, and it includes many well-known stones: emerald, green (owing to chromium), blue beryl, better known as aquamarine and prized for its brightness, and pink beryl, called morganite.

Garnet

We are very fond of garnets, because they have a high refractive index; in other words, they are stones that sparkle a great deal! Among the best-known garnets are mandarin garnet (orange), demantoid (whose fire surpasses that of diamond!) and almandine (brownish red).

Zoisite

Zoi-what? Zoisite! Like beryl, zoisite belongs to the silicate family. When it is blue, it is called tanzanite. It is an increasingly rare stone, and its value is rising accordingly. Little known at first, it owes its success to Tiffany, which began selling it in the late 1960s.

Quartz

This is a large family of very common stones, ranging from opaque to transparent. Among the best known are onyx (black), amethyst (purple), citrine (yellow), carnelian (orange) and chalcedony (blue)…

We hope this lesson has made you want to learn more about the families of stones. If you own jewelry set with any of them, we will be delighted to appraise it.

For any question or appraisal request, contact us.