Jewellers' Network

Category: Gemstones

Emerald and other varieties of Beryl

The occurrence of emerald is relatively rare because this mineral is only formed under very specific and unusual geological conditions.

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JPPE Manufacturing Jewellers

JPPE Manufacturing Jewellers
JPPE Manufacturing Jewellers is a Cape Town based family business that has been servicing the jewellery industry for 50 years.

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Sapphire – Birthstone of September

JPPE Cape Town Sapphires

As a symbol of Love and Purity, Sapphire makes one of the best birthstone gifts.

Almost as hard as a diamond and durable to wear everyday it makes a great alternative to diamond with engagement and anniversary rings. It’s found in most colours of the rainbow. Blue and Pink are the most popular choices.

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Save Tsavorite – Take our Basic Gem ID Course Now!

Oscar Wilde said many wise things, one of my favourite of which is “Life imitates art.” When he penned his now famous line in his 1889 essay, The Decay of Lying, he couldn’t possibly have known that over a century later, we’d be faced with imitation of a very different kind. 

Sadly, we are seeing far too much glass imitating tsavorite recently. This is a real tragedy, because tsavorite – the trade name for the emerald-green variety of Grossular Garnet that comes from Tanzania and Kenya – has become one of the most popular and expensive Garnets. It takes its name from the Tsavo National Park in the Serengeti, which is close to where it was first discovered. It was named by Campbell Bridges, its discoverer, and Henry Platt, president of Tiffany & Co. Continue reading…

Geminar by Gemlab

Come And Join Us At Our Geminar!

NOTE: We have one place available for the Practical Diamond Grading course from the 19th-21st July and the Basic Gem ID course on the 28th July 2017.

Regular readers of this newsletter may have picked up on the fact that not only am I personally passionate about all things relating to the fascinating world of gemstones, I’m equally passionate about stoking that enthusiasm and interest in others as well. Continue reading…

Jade, it’s varieties, substitutes and stimulants

Jade is a term used to describe two physically similar but chemically very different stones.

Whereas nephrite is a silicate of calcium and magnesium, jadeite is a silicate of sodium and aluminium. Sir Charles Hardinge, author of Jade Fact and Fable, proposed the names ‘amphibole jade’ for nephrite and ‘pyroxene jade’ for jadeite. While his suggestion was obviously meant to clarify the different nature of these materials it did not receive wide acceptance.

Jadeite generally exhibits cleaner brighter colours. It has a higher refractive index and is slightly harder and heavier than nephrite. Continue reading…

Upcoming Diamond Grading Course

The Gem Lab courses are becoming very popular and due to high demand, I have been asked to run another Practical Diamond Grading Course.

I am pleased to inform you that the next three-day Practical Diamond Grading Course will be held from the 19th – 21st July 2017.

Once you have completed the course you will be able to…
…have a better understanding of how the diamond industry works,
…answer questions like ‘blood diamonds’, diamonds as an investment, etc.,
…buy and sell diamonds with confidence,
…estimate the weight of diamonds set in jewellery,
…estimate the value of old cut diamonds,
…explain the 4C’s to customers,
and so much more.

For more information call me on 021 761 1746, or email

Warm regards,

Gem Alert – Fractured Synthetic Ruby

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.

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Invest In Yourself 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.

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Blue hues

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.

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Gemgold Gemstones

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

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.
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Coloured Stone Grading – Part 3


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…

2017 – New Beginning

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.

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Point cut

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.

Table cut

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.

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The Garnet Group

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? 

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Add some Christmas Sparkle – Zultanite


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.

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Natural top – synthetic bottom


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.

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Gem Alert – FAKE ROUGH


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.

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