The Semi-Precious Gemstones
I believe that the majority of women and many men love and appreciate the beauty of gemstones and fine jewelry. That’s why I’ve decided to devote several weeks to exploring them.
Last week, I told you a few things about the big five, the precious gemstones - Diamonds, Rubies, Sapphires, Emeralds and Natural Pearls. These are the gems that most people only aspire to own.
You may have or someday have a diamond engagement ring and you may inherit a small ruby or sapphire ring from your grandmother. As for acquiring a major piece of jewelry in precious gemstones, much less a collection, it’s probably only the stuff of dreams.
But! the good news is, there are the so-called semi-precious gemstones. Many of them are just as beautiful as the precious gemstones and some of them are arguably more beautiful. And the cost is much more reasonable.
There are literally thousands of them so I’m going to try to give you some information about the major three families of semi-precious gemstones: Beryl, Tourmaline and Garnet, plus one: Tanzanite.
So, let’s begin with the Tanzanite, the magnificent gemstone that nobody seems to know what to do about.
Tanzanite (Zoisite, 7.5 to 8 on the Mohs Scale of Hardness).
Tanzanite comes from only one small area near the Merelani Hills (AKA Mererani Hills) of Tanzania. It is a newcomer, having only been discovered in 1967.
Many people argue that Tanzanite should be classified as a precious gemstone because of its great beauty and extreme rarity. But, I think, largely because it has no romantic history about it and because Tiffany & Co. acquired exclusive rights to market it from 1968 to 1988, many of the powers-that-be in the gemstone world feel uncomfortable with this gemstone.
So it languishes as a semi-precious gemstone when it is really one of the most precious and beautiful gemstones in the world.
Its primary color is that of the finest blue sapphires, but it is trichroic (it has three colors). Depending on how the light hits it, it has strong violet hues and flashes of red.
Tanzanite is a clean stone with few inclusions. All of it is heat treated to bring forth its brightest colors.
Because the Government of Tanzania has never gotten together an organized marketing effort, the price of Tanzanite swings wildly, depending on which major jewelry house is interested in it at any given time. I’ve seen it sell for as much as the finest sapphires. That was about 10 years ago. It is currently selling for a fraction of that so, if you’re interested, this would be a good time to buy.
In addition, because the area of mining is small, new, quality Tanzanites might not be coming to market for much longer. And, unlike virtually all of the other significant gemstones, it cannot be synthesized.
Next: The Beryls (Beryl, 7.5 to 8 on the Mohs Scale)
Emeralds are the big brother in the Beryl family but you may not know that there is a whole range of other colors of Beryl.
Beryl is mined on all of the continents except Antarctica. It may be there too, we just don’t know about it. Most of the finest Beryls are currently mined in South America. With the exception of Emerald, virtually all Beryls are heat treated to burn out impurities, so they are very bright, clean stones.
Aquamarine is nearly as famous as Emeralds. Its color runs from a deep azure blue to a pale watery shade. As with most colored gemstones, depth of color and uniformity of saturation are the greatest determining factors in the price.
Morganite is another beryl you might know. Its color ranges from vivid rose pink to barely-there pink, with hues that run from peach to nearly lavender.
Green Beryl is the pastel green of the beryl family. It goes from spring green to palest green with yellow undertones. It also comes with blue undertones, but when it gets too blue, it becomes Aquamarine.
Heliodor or Golden Beryl is obviously the yellow beryl and it runs from palest citrine to nearly orange in some rare specimens.
Goshinite is the colorless member of the beryl family. It is sometimes used as a Diamond substitute, but since, other than its colorlessness, it shares very few other properties with Diamonds, it’s not seen that often. It is sometimes used as “pool of light” beads, but even in that application, it is uncommon because quartz is cheaper and just as pretty. Alas, poor Goshinite has never really found a purpose.
The Tourmalines (Boron Silicate, 7 to 7.5 on the Mohs Scale)
If you name a color it can be found in the Tourmaline family of gemstones. They are mined in Asia (primarily Sri Lanka), South America, North America and Africa.
Gem quality Tourmalines are almost always heated to produce bright, clean stones.
Like Beryl, some Tourmalines have earned their own names. You may know about them, but you may not realize they’re Tourmalines.
Paraiba is a bright, cerulean blue, often referred to as “swimming pool blue.” It was first discovered in the Brazilian Provence of Paraiba, hence the name. Interestingly, it was subsequently also found in Nigeria. If you reassemble the continents of Africa and South America as they once fitted together on ancient Earth, you will find that Paraiba and Nigeria were connected.
Indigolite (Indicolite) is a rich indigo blue and the most expensive of all Tourmalines apart from Paraiba. It’s rare and very beautiful. Even with heat treating it is hard to find a truly clean Indigolite, but when you find one, it will have been worth the search.
Rubellite is the red Tourmaline. The finest Rubellites are the color of Rubies, that is, an intense red with pink undertones. Rubellites also range from deep vibrant pink to nearly purple.
Chrome Tourmaline is the most desirable of the green Tourmalines. Chrome is the coloring agent in these bright green stones. They’re found in Africa and, less often, Russia - when they’re found at all. They’re very rare and beautiful.
Watermelon Tourmalines are bi-colored red and green. They’re cut where certain Tourmaline crystals turn from red to green and the good ones do look exactly like a piece of watermelon with rind. They’re very interesting and pretty, also affordable.
And now, on to Garnets (Silicate, 6.5 7.5 on the Mohs Scale)
Describing Garnets is a little more complicated than most stones. They not only come from all over the world, but they have families within the Garnet family. I’ll try to list them as simplistically as possible. This is necessary as the type of Garnet makes a world of difference in the look and price of the Garnet.
Those rather dull purply-red and brownish garnets you frequently see in Victorian jewelry are usually Pyrope and Almondine Garnets. They are the most common and the least expensive. They’re not all boring—many fine specimens of these types of Garnet are beautiful in red and orangy red.
But, the best Garnets are usually Spesartite and Grossular Garnets. These stones can cost twice as much or more than the more common types. But they’re worth it. These stones are second only to Diamonds in brilliance and they come in some pure, awesome colors. They’re mined in Kenya, Sri Lanka, Thailand, Arizona, USA, Brazil and India. Some of these are:
Tsavorite. I would say Tsavorites are the most beautiful green semi-precious stones and second only to all but the finest Emeralds. They’re named for Tsavo National Park in Kenya, near where they’re mined. They run from medium emerald to a truly brilliant grassy green.
The only drawback with Tasvorites is that they’re small. The largest Tsavorite I personally have ever seen was 22 carats, which is a giant of it’s kind, comparable to a 100 carat Diamond. It was not for sale. Most Tsavorites run to 1 or 2 carats and if you find one over five carats, buy it if you can because you’ll probably never get another chance.
Hessonite is a brilliant gemstone that runs from a lively cinnamon-brown, through orange, on to bright red and even apple green. The orange variety has been branded as ‘Mandarin Garnet’.
Rhodolite is the bright pink to ruby red Grossular Garnet. It was named for the former state of Rhodesia in Africa, near where it is most commonly mined. Some people also claim the it was named for the flower rhododendron. Like all Grossular Garnets it is brilliant and lively.
Although Rubelite Tourmaline is better known and I think it’s beautiful, I would choose a Rhodolite over it any day. But, again, like the Tsavorite, Rhodolites tend to be small. They're not as hard to find in larger sizes as Tsavorite,, but they’re still pretty rare.
There are so many other semi-precious gemstones I could name - from Lilac Kunzite to Australian Opals, but the ones I’ve mentioned are the most likely to find their way into your jewelry box.
If I’ve peaked your interest in gemstones then I’ve done my job.
Next week, I’ll discuss finished jewelry.
Gabrielle