The Most Valuable Characteristics of August Birthstones

The vivid green of the peridot,with just a slight hint of gold, is the ideal gemstone colour to go with that light summer wardrobe. No wonder 

since the peridot is the gemstone of the summer month of  August.

The peridot is a very old gemstone, and one which has become very popular againtoday. It is so ancient that it can be found in Egyptian jewellery from the early 2ndmillennium B.C.. The stones used at that time came from a deposit on a small volcanicisland in the Red Sea, some 45 miles off the Egyptian coast at Aswan, which was notrediscovered until about 1900 and has, meanwhile, been exhausted for quite sometime. Having said that, the peridot is also a thoroughly modern gemstone, for it was notuntil a few years ago that peridot deposits were located in the Kashmir region; and thestones from those deposits, being of an incomparably beautiful colour andtransparency, have succeeded in giving a good polish to the image of this beautifulgemstone, which had paled somewhat over the millennia.

 

Spectacular 'Kashmir peridots'

But suddenly, in the middle of the 1990s, the peridot was the big sensation at gemstonefairs all round the world. The reason? In Pakistan, up on an inhospitable pass at some4000 metres (13,120 ft.), a sensationally rich deposit of the finest peridots had beenfound. In tough climatic conditions which permitted the gemstones to be mined onlyduring the summer months, the unusually large, fine crystals and fragments werebrought down into the valley. These stones were finer than anything that had ever beenseen before. And the deposits were so rich that the demand for peridots can, for thepresent, easily be satisfied.

 In order to emphasise the special quality of the peridots from Pakistan, these stones areoffered as 'Kashmir peridots', following the famous Kashmir sapphires. Creativegemstone cutters have succeeded in cutting some fascinatingly beautiful one-off stonesof more than 100 carats from some of the large, fine, clear crystals with their magnificent rich green!

 

How green? It all depends on the iron

This gemstone has no fewer than three names: 'peridot', 'chrysolite', from the Greek'gold stone', and 'olivine', for the peridot is the gemstone form of the mineral olivine. Inthe gemstone trade it is called 'peridot', derived from the Greek word 'peridona', whichmeans something like 'to give richness'.

The peridot is one of the few gemstones which come in one colour only. The rich, greencolour with the slight tinge of gold is caused by very fine traces of iron. From a chemicalpoint of view, peridot is an iron magnesium silicate. The intensity of the colour dependson the amount of iron actually present. The colour itself can vary over all shades of yellowish green and olive, and even to a brownish green. Peridot is not particularly hard- only 6.5 to 7 on the Mohs scale - but it is easy to look after and fairly robust. Peridotcat's eyes and star peridot are particularly rare and precious.

The most beautiful stones come from the border area between Pakistan and Afghanistan. However, the peridot as a gemstone also exists in Myanmar, China, theUSA, Africa and Australia. Stones from East Burma, now known as Myanmar, have avivid light green and fine inclusions with a silky shine to them. Peridot from Arizona,where it is popularly used in native American jewellery, often has somewhat yellowish or gold-brown nuances.

 

Uncomplicated, but not for the cutter 

The peridot is cut in accordance with its crystal shape, mostlyfaceted or in classical table cuts, or round, antique, as an

octahedron or oval. Smaller crystals are cut into standardised series stones, larger onesinto imaginative one-offs. Cabochons are made if the material contains more inclusions,for the domed cut brings out the fine silky shine of the inclusions to their best.

The cutters know full well that this gemstone is anything but easy to work with. The rawcrystals can be very tricky and may crack easily. There is often a good deal of tensionon the inside of the crystal. But once the cutter has succeeded in removing the coarser inclusions, the peridot is a precious stone with good wearing qualities which does notcall for any special care.

 

An ideal summer stone

 The peridot adds a wonderful variant to the colour spectrum of green gemstones.Increasingly, it is processed not only to one-offs, but also for use in series jewellery. Andsince the world of fashion is just in the process of rediscovering its love for the colour green, the popularity of this rich green gemstone is also very much on the up.

 Thanks to the rich finds in Pakistan and Afghanistan, there is enough raw material onthe market, so the 'right stone' can now be found to cater for each individual taste andeach pocket. Large, transparent stones of an intense colour are, however, rare andcorrespondingly expensive. The peridot is a gemstone that you should definitely get toknow better. Its fine pistachio to olive green is the perfect complement to a fresh, lightsummer wardrobe

 

Once upon a time, peridot was more than just a vibrant green gemstone, it was a manifestation of the sun and a guardian against night terrors and evil spirits. And while the Ancient Egyptian furore around this magical gemstone may have died down over the millennia, there are still plenty of passionate advocates for exceptional green peridot. One such advocate is Fuli Gemstones, a mining, processing, marketing, sales, import/export and consulting business with ownership over the world’s largest peridot deposit: the Yiqisong Nanshan Peridot Mine in China. Discovered in 2016, this new deposit of gem quality peridot is located in the Yiqisong District, approximately five kilometres north-east of the previously known Dashihe peridot mine near Jiaohe. The deposit covers an area of 5.1 km2 and is hosted by Neogene basalts in the Dunhua-Mishan fault zone. The mine is conveniently located along connections to Yanji Chaoyangchuan Airport and the exit of the Yuwu expressway in Huangsongdianzi Town, in addition to having a forestry road that connects the mine area to the nearby Dianzi town, making it unusually accessible. Since its discovery, the mine has been studied and developed by the Yanbian Fuli Peridot Mining Industry Co. Ltd, now known as Fuli Gemstones. “The significance of the Yiqisong Nanshan Peridot Mine is the quality, clarity and colour of peridot being discovered,”

 

explains Pia Tonna, Chief Marketing Officer of Fuli Gemstones, who has previously worked for Gemfields and Swarovski. “The reserves are estimated at approximately 501 tonnes of gem quality peridot, therefore making this mine of huge significance and importance with a superb location.” Tonna continues: “The mine is a tunnel, as opposed to an open-pit, with far less rock removal. Our intention is to use the waste material for the road and rail infrastructure of China. We are also in discussions with a company within the environmental space, who are working on a project that envisages using large volumes of olivine/olivine-bearing rock for their mission.” A number of factors have come together to make this mine of real significance for the global gem industry, including findings by the Gemmological Institute of the China University of Geosciences (Wuhan), which is also a Gem-A Accredited Teaching Centre; the combined experience of the Fuli Gemstones operations and management team; the conditions within and accessibility of the mine itself; and the quality of peridot rough produced by the mine. As Tonna explains: “The ore body is of a regular tabular and uniform thickness, making it very suitable for high-tech, precise and high-efficiency mechanised mining operations. Low operating costs, coupled with high-quality and large reserves, gives Fuli Gemstones a clear and competitive advantage.” Studies suggest that, different from the common yellow-green peridot found in other geographical production areas available to the market, gems produced at the Yiqisong Nanshan Peridot Mine are characteristically vibrant grass green with strong hue and saturation. In addition, they boast excellent clarity with few cracks or flaws.

 

A DISTINGUISHING TRAIT Gem-A Gemmology Tutor, Charlie Bexfield FGA DGA EG, explains more about double refraction in peridot. Peridot is an optically anisotropic material. This means that when light enters the gemstone it is split into two rays each travelling at 90 degrees to the other, but in different directions, and at different speeds. We call this double refraction. Due to the varying speeds of each ray, one ray will either be refracted more, or less. The faster the ray, the more it will refract. Sometimes the difference between these rays is so great that when looking into the stone it appears as though everything is doubled. Peridot is a good example of this. The distance between each ray is measurable with a refractometer and when they are at their furthest points apart, we refer to this difference as the birefringence. Peridot has a relatively high birefringence of 0.036. Due to peridot’s high birefringence we can see doubled images when looking into the stone with a loupe. We can use this to help with the identification because there aren’t many yellowish-green gemstones which show such strong doubling. Always conduct other tests before concluding though. Sinhalite, as an example, can be a similar colour and has a birefringence of 0.038 which is why testing is so important.

 

As an integrated company, Fuli Gemstones is tapping into the retail market, as well as enhancing its trade and consumer-facing image with new strategies that are designed to promote the beauty of peridot. “We offer designers and brands bespoke cutting,” says Tonna. “We want to work collaboratively with young creative talent to help them push boundaries in jewellery design – we wholeheartedly believe in creativity – our company ethos is ‘natural innovation’.” She continues: “Our gemstones are natural and require no treatments. We want to innovate through our cutting to showcase the highly refractive nature of peridot.” Part of Fuli Gemstones’ efforts to promote peridot is to develop a grading system for the gem, based on colour, clarity and carat in the rough. While details have not yet been announced, Fuli Gemstones is said to be working with “leading labs and industry experts” to develop a “peridot profile” that may serve to create a value structure. At the same time, the company is plotting a peridot museum to both educate visitors and demonstrate how corporate social responsibility measures are supporting sustainable mining among local communities. Looking ahead, Fuli Gemstones has grand ambitions to become a gemstone group, meaning they are “actively looking at new, unique assets and opportunities globally,” according to Tonna. She continues: “We have a clear strategy and timeline that we are following, and we will begin advertising and promotion in the second half of 2020. August is the birthstone month of peridot and it’s the perfect time to shine a light on our remarkable gems.” With operations in Beijing, Jilin Province, Hong Kong and London, Fuli Gemstones is on a mission to champion peridot, inspire fine jewellery designers and increase recognition among end consumers. While COVID–19 may have hampered its growth plans, we have no doubt that this forwardthinking company will make its mark and secure a new appreciation for this ancient terrestrial and extraterrestrial gem.

 

NEED MORE INFO?

Discover more detailed research surrounding peridot from the Yiqisong District in an insightful report by Zhiqing Zhang, Min Ye and Andy H. Shen, featured in The Journal of Gemmology, 36(5), 2019, pp. 436-446. Gem-A Members can search: gem-a. com/jog-contents-volume-36-issue-5 “Peridot from Neogene olivine-bearing basalt in the Yiqisong District of Jilin Province, China, and from North Korea are available in the global gem market. We characterised 100 stones from each of these two localities, and found similar RI, birefringence and SG values, but slightly different colour ranges, UV-Vis-NIR spectral characteristics and internal features. The most common inclusions in both the Yiqisong and North Korean samples were ‘lily pad’ discoid fractures; also present were diopside, chromite, enstatite and lizardite (the latter two were observed only in Yiqisong peridot). Chemical analyses indicated that most samples had forsterite contents ranging from 89.4 to 92.2 mol.%, with a trend toward slightly higher Fe in the North Korean samples. Statistical processing of the trace-element data with Fisher linear discriminant analysis (Fisher-LDA) showed that Al, Zn, Ti, Na and Ge are useful for separating peridot from these two localities.