Synthetic rubies are giving the slip to those in the trade since mankind assigned value to pieces of shiny metal and brightly coloured stones, attempts have been made to duplicate Mother Nature’s handiwork.
The Verneuil Process of producing synthetic gemstones is the most common synthetic we see today.
Benjamin Franklin famously said, “The only thing more expensive than education is ignorance.” Profound, yes, and still absolutely true over two hundred years later. But improving our education doesn’t only mean attending school or university. As intelligent, curious adults, we should always be looking for ways to increase our knowledge and foster a love of life-long learning that enriches our lives and grows our minds.
Blue hues – Arthur Thomas
Agate blue lace
Viable deposits of this attractive agate with its delicate lacy blue and white banding occur in both South West and East Africa.
This name, derived from the Greek for “I am misleading” is probably a reference to its marked resemblance to the harder and more valuable mineral, beryl. Sapphire blue apatite is sometimes given the varietal name Moroxite it was produced as a by-product of emerald mining at the Cobra Mine, Phalaborwa. There are mines in Madagascar that produce apatite in a wide range of hues including the very collectible electric-blue and neon-green varieties. Continue reading…
The Turkish deposit remains the world’s only source of Zultanite (color-change, gem quality diaspore) and is recovered using only environmentally safe mining techniques.
Zultanite was named in honour of The Ottoman Sultans that ruled a vast empire for many centuries.
The GIA classifies Zultanite as a Type II transparent gemstone. Zultanite almost always contains inclusions.
With more than 20 years of experience in the gemstone industry, GemGold Gemstones, is still going strong!
What once started as a small business, with Andre de Klerk, buying and selling rough gemstones, has flourished over time, into a substantial and reputable gemstone business. Some might say the magic came to life, once Andre’s wife, Errolene, joined him. Errolene quickly found her niche and specialised in the selling of cut gems, in the jewellery industry. Continue reading…
Inclusions African Gemmological Laboratory
In gemmology an inclusion is a clarity characteristic, enclosed within a gemstone, or breaking the surface from the interior.
Inclusions are normally perceived as being a negative feature in a gem as they usually devalue a stone, except in the case of ‘horsetail’ inclusions in demantoid garnets and phenomenal gems where the inclusions cause the phenomena.
Welcome to part 3 of our mini-course on coloured stone grading. Last week we looked at the key role colour plays in assigning a grade value to a gemstone. Today, we’re diving into clarity. Continue reading…
New Courses, New Prices, and a New Approach to Learning Gem Identification
The value of a gemstone is tied to a number of factors. Telling what these are takes a trained eye. A gemstone is only worth what it can be sold for, and that depends heavily on whether its authenticity can be proven. The best way to prove the worth of the stones you’re selling is to ensure each one is certified by an internationally recognised professional certifying body. Including a printed certificate of authenticity with your gemstones means you’ll be able to close more sales – and for a higher value.
This earliest of diamond “cuts” simply involved polishing away any blemishes on the faces of a diamond octahedron. Legend has it that the association of diamond with love came from the practice of French courtiers to use a point diamond to write messages on inconspicuous palace windows arranging assignments, hence engagement rings.
The table was a very early and practical diamond cut. It merely amounted to grind-ing and polishing away a heavily included or damaged point of a diamond octahedron.
The garnets, a large and rather complex family group, may vary considerably in their chemical composition, physical and optical properties.
For the gemmologist this means that there is an additional step in the identification process. Firstly he must determine if the properties of the unknown place it within the garnet group?
Secondly to which species does it belong and then finally what variety is it?
The term “diamond in the rough” has become a familiar companion in our daily lexicon. It’s used to describe a number of different scenarios – anything from a surly-seeming character who’s really quite charming once you get to know him … to a thing of great value, which has yet to be discovered.
Zultanite falls squarely into the latter category. It’s one of those almost-forgotten gems that, if marketed properly, can add some genuine sparkle to your sales this Christmas.
Last week I showed the star rubies and sapphires that can be grown using the Verneuil process. They can be exquisitely beautiful, but no less fake for all that. It’s a classic case of true beauty being more than skin deep!
It’s also very good reason to make sure you get your gemstones checked before
you sell them to unsuspecting customer. Better yet, if you can, get them checked before you buy them!
Rubies and sapphires are not the only gems to get the synthetic special treatment. Really, anything that has integral value will soon find itself the subject of knock-offs, copies, look-alikes, wannabes, and fakes.
Finely polished tourmaline is simply exquisite. Glinting happily in every hue of the rainbow, it’s easy to see why this exquisite stone is gaining popularity. Of course, as it becomes more popular, it becomes more expensive. The higher the demand, the higher the price. Unfortunately, the more valuable something becomes, the more tempting it is for the unscrupulous. So it’s no surprise that con artists have started peddling fakes, trying to pass it off as the real thing. (Although it is disappointing, of course.)
We came across an example of this just the other day, when a client bought a bag of rough tourmaline. Or so he thought. It was actually a bag full of glass. This rough is very convincing, though. It’s no surprise my client was duped into thinking it was the real thing.
Ruby is generally found in a metamorphic environment especially in such rocks as granular limestone, mica or chlorite schists, however it may also occur as a constituent of aluminous igneous rocks. Ruby is a variety of corundum, which is the second hardest natural mineral after diamond. Being both hard and heavy gem corundum rough is most frequently recovered from placer deposits. Traces of chromium are responsible for the superb blood-red hue of fine material.
Some jewellery firms issue their own certification. The idea is that this saves time and makes it easier for buyers to – well, buy.
The question is, can these firms really be trusted to give an unbiased certification?
Not long ago, I was asked to double-check the certification of a diamond. It had already been certified by the well-known establishment that sold it. When I examined the diamond, I found that the GIA (Gemological Institute of America) reference number had been lasered onto the girdle. That meant I could look it up online.
Communication is so important when a group of people are working together for a common goal. We all know what happened to the tower of Babel when God changed the languages of the workers. In that vein I thought we could go over some of the basic terms used in our trade in order to ensure that we all speak the same language.
This series of articles briefly examines how and where gems originate.
In the case of diamond the long-standing mystery of its source was finally thought to have been resolved in 1870 with the first discovery of a diamond bearing kimberlite in the South African Free-State.
However modern research has revealed that kimberlite is not the matrix in which diamonds formed. In fact diamonds are formed in the very active high pressure and high-temperature zone that lies between the Earth’s solid crust and its outer mantle (Fig 3). That said, it should be noted that the occurrence of diamond is rarely associated with typical volcanic activity.
The following code letters are employed in gem certification in order to indicate the nature of any treatments that may have been applied to the gemstone to enhanced its colour, appearance or durability.
Optical phenomena in gemstones may take a number of forms
A gem exhibiting a billowy floating light that appears to emanated from below its surface is displaying adularescence. This term is derived from “adularia” the historical name for moonstone. “Schiller” is another term that may also be employed to describe this effect that is the result of the presence of fine lamellar twinning within the stone.