Gems in Tribal and Ethnic Jewellery

The most widely used, of the non precious gems in tribal and ethnic jewellery are coral, turquoise, amber, agate, carnelian, lapis lazuli, malachite, amazonite, onyx and other black stones. While not natural gemstones, glass, ceramics and man made trade beads are also widely used. All these gemstones have been traded and and set into tribal  jewellery for thousands of years.
From diamonds to clay, virtually all gemstones used in jewellery have been ‘treated’ or ‘enhanced’ in some way. The most obvious and most accepted form of enhancement is the cutting or shaping and polishing of a gem.
Now days there are many different treatments available, some quite simple such as dyeing, others more complex such as laser treatment. In some cases  a treatment has become so routine that dealers take it for granted and it is only when the gem has not been treated that it is disclosed. A classic example of this is the heat treatment of sapphires. This improves the colour and clarity of the sapphire and is standard treatment in perhaps > 95% of all sapphires.
There are of course many treatments used that are not considered normal for a particular gemstone and these treatments will usually have an effect on the gemstone’s value and should be disclosed.

Turquoise.   Turquoise is perhaps the most widely used gemstone in tribal jewellery. It is well know as a bright light blue opaque gemstone with dark veining. It can vary in colour from white through to shades of blue and green. The most prized gems display a pure vivid light to mid blue colour. However it is more common to find cut gems displaying variations in colour, with attractive veining and numerous patches of host rock material.
Turquoise is found in many countries throughout the world.  For thousands of years it has been mined in countries such as Iran, Turkey, the Sinai Peninsula, China, the Himalayas and Afghanistan. It also occurs in South America and the most significant source today is in the South West United States, in Arizona, New Mexico, Colorado and Nevada. In the US it is the most coveted gemstone used by the silver jewellery making artisans of the indigenous Navajo and Zuni people. Like coral, turquoise is not that hard to identify from imitations once you gain a “feel” for the material, however it is extremely difficult to distinguish natural from treated material. Using a 10x loop  the surface  of turquoise displays a consistent smooth colour with fine white spotting and any veining should be random in design.
There is a lot of imitation and treated material available. In most case it arouses suspicion because it looks too good, too consistent in its colour and too repetitive in its veining. The most common imitations of turquoise are either dyed howlite or dyed magnesite. Howlite with similar veining patterns can be tricky, look for dye stains along vein lines. A small drop of HCL acid will cause magnesite to effervesce and howlite to turn green. Glass and plastic is also used as an imitation. Under close examination, bubbles in glass swirling in glass and plastic are often evident, further the translucency of glass just doesn’t look like real turquoise.
The most common ‘treatment’ of turquoise include ‘reconstitution’ and ‘stabilisation’. Reconstituted turquoise is made by grinding up small pieces of low quality turquoise which is then pressed and bonded with dyes and resins, (glues), into a sold mass which is then cut into gems. While technically it is turquoise, bonded with glues, in my opinion reconstituted material should be categorised as an imitation because it is far from natural. Also some reconstituted ‘turquoise’ is made from cheap alternatives such as howlite or Magnetite which is ground, dyed and bonded and this product is most certainly an imitation. The reconstituted product tends to raise suspicion because it can look too consistent, too good to be true.
Natural turquoise will change and or fade in colour over time and it is often too friable to be cut into a solid gemstone. To counter these problems most turquoise today is ‘stabilized’. Stabilization is a process whereby a resin, epoxy or a glassy substance, (sodium silicate), is impregnated under pressure into the turquoise. This enhances the colour and makes the turquoise more solid and durable. There are varying degrees of stabilization, the most extensive approaches reconstitution in that highly friable low colour material is dyed and bonded together. The least invasive process simply enhances the durability of good coloured reasonably solid material.
The fact is most turquoise today has been treated significantly and one should assume this unless they know it not to be the case. Most untreated natural turquoise today comes from the mines of South West United states, the Sleeping Beauty and Kingman mines are well know examples, understandably this material demands a premium.

Coral.   Like turquoise and amber, red and pink coral has been used by tribal artisans in jewellery for thousands of years, it was a highly prized commodity traded along the ancient Silkroad routes. Like amber and turquoise as well as being pretty coral was believed to posses mythical powers to protect and heal.
For thousands of years coral has been harvested from the Mediterranean sea especially around the Italian and Sardinia coast and  along the North African coast in the Mediterranean and Atlantic oceans. More recently it is harvested in deep water around Japan and Taiwan.
While red and pink are the most popular coral is also found in other colours, white, black, and gold being the most common.
Many cultures have used coral, turquoise and amber in their jewellery. They have always been popular with Himalayan people and while I have read that the Tibetans first discovered the beauty of red coral from deposits in the Himalayas I think this is somewhat misleading. Coral, shells and fish bones deposited over millions of years are eventually, compacted by geological forces into limestone. While limestones will exhibit marine life fossils including coral it is not the same as sea coral. Fossil coral while attractive is usually white to brown and looks more like stone than coral. While Himalayan peoples may well have used fossil coral it is not the same as the red and pink sea coral so commonly scene in their jewellery today. The red and pink corals used by the Tibetan & Nepalese people for many hundreds of years came from Silk Road traders, from China and from the rich deposits of the Mediterranean.
Bamboo Coral is commonly used today as a substitute for the now scarce and protected precious red Mediterranean coral. Bamboo Coral, so called because in its natural state it looks like bamboo, grows in deep oceans and is a white in colour with black bands.  It is dyed red or pink to look like precious red or pink coral. today most coral on the market is dyed bamboo coral.
Once one gains a “feel” for coral it tends to be reasonably easy to from its imitations. It usually shows at least some pitting and texture, it is light in weight and even when highly polished does not exhibit a glassy look. Imitations of coral include dyed shell and bone, glass, ceramics and plastics. Reconstituted coral, see turquoise above, is also used.
Corals, shell and bone are made of calcium carbonate and will effervesce if touched by a small drop of hydrochloric acid. A more practical test is to place the piece in vinegar, a weak acid, for just a short time. If bubbles, (effervescence), appear on the surface it shows it is calcium carbonate and therefore may be coral, shell or bone but not glass or plastic. Plastic will melt with a red hot needle and often shows swirl markings.  Glass may exhibit tiny bubbles under magnification; it may also show mould or swirl lines but will not show the pitting or texture of coral. Glass being harder also tends to display has a more polished look and unlike coral will not scratch easily.

About amber and copal.   Amber and copal have been burned as incense and used in jewellery for thousands of years. Like coral and turquoise amber was a highly prized commodity traded along the ancient Silk Road routes.
Amber is formed from prehistoric tree resin, (not sap), that has been transformed over tens of millions of years by a process called polymerisation where the resin slowly loses its oils and hardens into the plastic / resinous like substance we know today as amber. Copal is a type of immature amber. It may be only a few hundred to a few million years old and therefore has not fully undergone the polymerisation process required to create true amber.
Amber and copal deposits can be found in many locations throughout the world. The vast majority of amber was and still is mined from the 40 to 50 million year old deposits in the Baltic region of Poland and Russia. Until very recently only copal was found in Africa, historically from Tanzania and the Congo and more recently in Madagascar. Some twelve years ago a 95 million year old amber deposit was discovered in central Ethiopia.
While most people think of amber and copal as a honey coloured transparent substance it also occurs in black, red to plum, shades of green and blue, almost colourless and all shades of yellow, orange and brown. It can vary from clean and transparent to being full of inclusions to opaque.  Inclusions may include prehistoric insects or leaves that were caught in the sticky resin when it oozed from its tree.
The most common materials used to imitate amber are various forms of  synthetic resins and plastics and horn. Amber is also available as reconstituted, (pressed), amber, see in Turquoise above. It is not easy to distinguish amber or copal from each other or from their imitations. It will usually require the results from several tests to establish a conclusive identification. The most common tests are:- 1. The red hot needle test which will not easily penetrate amber or copal and should create a pleasant wood odour.  A red hot needle will usually easily penetrate a plastic, melting and blackening it, giving off a chemical odour.  2. True amber will float in well salted water. Most copal and amber imitations won’t. 3. When rubbed briskly with a cloth amber readily becomes electrostatically charged and will attract small pieces of paper to it, however this can also occur, to a lesser degree, with other materials.
4. A drop or two of Acetone, (nail polish remover), will not, or will barely affect, amber but will dissolve most plastics and copal making them tacky or sticky. 5. Under UV light true amber will glow a yellow, orange, green or blue colour while copal’s glow will be faint and plastic and synthetic resins tend not to glow at all. 6. If you have a refractometer the refractive index or RI of amber and copal is around 1.54

 African Amber.  So called “African Amber” is prized by the Berber people of North Africa and collectors of tribal jewellery. Very old, rare examples can be worth thousands of dollars, however, a word of caution, despite what many sellers and websites would have you believe “African Amber”  is almost never true amber nor is it copal, ( see about amber and copal above).  From my experience I would guess that greater than 95%  of so called  “African Amber” is newish man made pieces, made from resins or plastics. It is true that because of its entheogenic history, authentic old African, man made faux amber, can be quite valuable. However it is rarely worth the hundreds or thousands of dollars that some sellers claim. I would suggest you ask for an authentication certificate from a reputable laboratory before buying necklaces or items which are claimed to be real amber or copal.
Older beads, may crack and are stapled together with white metal strips to stop them from cracking further. This adds to their desirability as it helps to authenticate their history and adds an attractive and interesting look to a bead or necklace. However, once again buyers must be cautious because new beads are also treated in this fashion.
I would advise never to pay large amounts of money for “African Amber” necklaces unless you are absolutely sure about what you are purchasing.

Carnelian, Agate, Onyx and the quartz familytribal-jewelry-carnelian-ri
Like Chalcedony these three gems are all colour variations of the same substance, they are all cryptocrystalline quartz. Quartz is made of silica, (SiO2), and it is the most abundant mineral on Earth accounting for a very large group of semi-precious gemstones which are found throughout the world. Quartz can appear in its transparent or crystal form or in its cryptocrystalline, (a mass of microscopic crystals) opaque or mostly translucent form.  
tribal-jewellery-agate-ringQuartz occurs in many colours,  for example, if white it is known as milky quartz, if green it is known as green chalcedony or if green and containing tiny mica specks it is called aventurine.  If pink, it’s rose quartz, if purple then amethyst, if orange to orange brown then is called citrine or if an orange red it is known as carnelian, if black it is called onyx. If a specimen displays bands of colour it is known as agate and where silica replaces the original asbestos it can result in Tiger’s Eye.
All quartzes are reasonable hard and tough stones and therefore can be shaped and well polished so they are most suitable for use in jewellery.
There is often no need to artificially treat the quartzes however htribal-jewellery-onyx-beadseat treatment, dyeing and irradiation to improve the colour is common.  Most citrines are the result of heat or irradiation treatments. 
Because quartz gems are quite inexpensive generally when being traded little if no consideration is given to the question of whether they are treated or not.   

Lapis Lazuli, Malachite and Amazonite
tribal jewellery malachiteLapis lazuli, also commonly called lapis, is a beautiful mid to dark blue coloured stone made up dominantly of lazurite with varying quantities of other minerals such as sodalite and calcite. In particular lapis is well known for the often bright golden to greyish flecks of pyrite, (fool’s gold), disseminated throughout. Like other tribal jewellery gemstones mentioned above, Lapis has been a popular ornamental and jewellery gemstone for thousands of years; there are many surviving examples from the ancient Egyptian civilizations. It hastribal jewelry Lapis lazuli been mined historically to the present day in Afghanistan and Iran and more recently at Lake Baikal in Russia it is also mined in several other countries including the Americas 

Lapis Lazuli treatments include stabilisation, reconstitution and dyeing as discussed with turquoise, see above. However as good quality lapis is still relatively plentiful treatment or enhancement is not so common.

tribal-jewellery-MalachiteMalachite is a beautiful mid to dark green copper carbonate stone which usually exhibits circular, (botryoidal), and wave like colour banding. It is often associated with a beautiful dark blue stone, of similar composition, called Azurite which looks similar to lapis lazuli without the flecks. 
Malachite is associated with copper deposits and is found throughout the world. Surprisingly malachite is not so commonly seen in tribal jewellery perhaps tribal jewelry malachite beadsbecause it is relatively soft and therefore scratches quite easily. It has however always been popular as an ornamental stone sometimes being carved into enormous ornaments or sculptures, measuring metres in dimension.
Malachite is rarely treated because good quality specimens are still plentiful however it is sometimes subjected to stabilisation and dyeing.

Amazonite varies in colour from a light to mid greeny blue with a vague white Amazonitemottled appearance; it is usually opaque in tribal jewellery but also can occur in a translucent form.  It belongs to the huge and prolific group of minerals called feldspars.
Historically Amazonite was mined from the Ilmen Mountains in Russia which accounts for its use in Middle Eastern tribal jewellery. It also occurred in smaller deposits throughout the ancient world. Like other tribal gemstones it was used by the ancient Egyptians and in North Africantribal-jewellery-amazonite- tribal jewellery.
Amazonite is not a valuable semi –precious gemstone, consequently it is rarely, if ever, subjected to enhancement treatments.

 As always your comments and or questions are most welcome.

 

 

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Buying Diamonds – A practical, buyer’s guide to diamond grading.

Unlike all other gemstones diamonds have a universally accepted grading system that identifies and grades diamonds extremely accurately. However be aware, accurate grading requires a very high level of expertise, as a consequence, unfortunately many diamond grading certificates are not accurate.

There is one laboratory that is universally accepted as the world’s number one grading laboratory, it is the Gemological Institute of America, known as the GIA.  There are many other laboratories throughout the world, some are excellent, some poor, however only one, the GIA, is recognised internationally as the “bench mark”  The second most universally respected laboratory is the Diamond High Council of Belgium known as HRD. Diamonds are regularly traded worldwide, without inspection, based purely on their GIA or HRD diamond grading certificate specifications.
In Australia the most recognised and reliable laboratory is the Gem Studies Laboratory, based in Sydney, it also known as GSL.

It was the early 1980’s when grading certificates began to be relied on for identifying, grading and valuing diamonds.  This was a great step forward for the consumer because prior to this there was no reliable way to compare “apples with apples” Since the 80’s the grading system has been continually refined to a point where if carried out correctly it is extremely precise.

Most people, who have some interest in diamonds, have heard of the “4C’s”  This stands for:-  1. Carat Weight  2. Cut  3. Clarity  4. Colour.  While these are the well know grading criteria there is also an important fifth criteria, referred to as Fluorescence.

1. Carat (ct) – or the weight in carats; not to be confused with gold where the term carat refers to the purity not the weight ( see About silver, gold and metals in tribal jewellery). There are 100 points (pts) in 1ct and 5cts in 1 gram. In the trade diamonds are wholesaled, (as are all gemstones), at a US$ per carat, (pc), price and the bigger a diamond is the more per carat it will cost.  So a 50pt or ½ ct round diamond may wholesale for say US$4,000 pc, ie $2,000 for the stone, while a 1ct diamond of the same cut and quality may wholesale for US$9,500 pc, ie $9,500 for the stone. So while a 1ct diamond is twice the size of a 50pt diamond it may wholesale for nearly 5 times the price of the same quality 1/2ct diamond. This leap in price is because larger diamonds are rarer. A principal that applies to most gemstones but not all and usually not to the same degree.

2. Cut – relates to how precisely, a particular shape is cut and polished. This affects the way light is reflected and refracted, (separated into its spectrum colours), through and out of the diamond, ie how much the diamond will sparkle, often referred to as its “fire.”
The most common shapes that diamonds are cut into are, Round, also known as Brilliant cut; Princess cut and Emerald cut, these are square or rectangular shapes; Oval cut; Pear cut, also referred to as Drop shape, and Marquise cut which is the boat shape with pointy ends.  There are other cuts which are generally referred to as Fancy Cuts.  By far the most popular shape and the most expensive is the Round or Brilliant cut.
While cut is most important don’t be swayed by sellers who claim they have the best cut. As mentioned in the 4th paragraph above the development of accurate certificates has enabled consumers to compare “apples with apples” This exact comparison has meant that sellers have tried to establish a point of difference, other than price, between their diamonds and their competition. Because cut is the most complicated of the 5 grading criteria sellers use the cut as their point of difference often giving a fancy name to “their cut” which they might propose is the best cut of all. Be assured that if the diamond has a GIA certificate which says the diamond has excellent proportions, excellent polish and excellent symmetry, ( known as an ex, ex, ex diamond) then you have one of the best cuts and you really don’t need to concern yourself about cuts with fancy names. Note, I am not suggesting you should only buy an ex, ex, ex diamond, (for which you will pay a premium). There other other grades and combinations of all grades, such as Good (G) or Very Good (VG) which still make for a well cut diamond. However as they are not in the excellent category such diamonds should be selling at a lower price and therefore depending on your budget priorities may be more appropriate for you.
A well established term you are likely to hear with regard to the cut is “hearts & arrows.” This refers to a pattern of hearts and arrows that can be seen in some very well cut round diamonds when looking through a special viewer. This does confirm that the diamond is of excellent proportions & symmetry,  however a diamond can still be an ex, ex, ex diamond and not exhibit a hearts and arrows pattern.
Marcel Tolkowsky developed the original 58 facet round brilliant cut diamond in 1919. This has since developed into the Ideal cut as shown at right. If the culet, (bottom point), is not faceted, which is not uncommon, then there are 57 faces. Today the girdle is also often faceted with many faces which is certainly an attribute provided the girdle is not too thick. The convention is not to count those girdle faces on top of the 58.
To conclude cutting, there is not one perfect cut. Within the realm of the ideal cut there is some tolerance with the proportions, some small variations that will still produce an ex, ex, ex cut diamond.
I quote from the GIA website www.diamondcut.gia.edu/  “The most exciting and reassuring conclusion of our research is that there is no single set of proportions that define a well-cut round brilliant diamond. Our research has shown that many different proportions can produce attractive diamonds”.

3. Colour – Diamonds occur in nature in many “fancy” colours such as red, blue and green, these very rare and therefore demand extremely high prices. Most diamonds occur in various shades of white, yellow or brown. Very white or very yellow (fancy yellow), diamonds are also quite rare and therefore also command a premium.
White diamond colour is identified by a letter of the alphabet. D is the top colour, the whitest, or to be more precise, the most colourless. The grading system then works its way down the scale through E, F and G which are all “white” stones but each with the faintest increasing ting of yellow or brown. This change is so subtle it can only be properly judged by comparing the diamond against diamonds of known colour in a controlled light environment.  By J colour the colur tinge becomes apparent even to the untrained eye and so on as it goes down the alphabet as the diamonds become more and more yellow or brown and correspondingly less valuable.

4. Clarity refers to marks that may be in or on a diamond. The clarity grades are, Internally Flawless or IF, Very Very  Slight mark one or VVS1, then VVS2, then VS1 and VS2 then Slight Inclusion 1 or SL1 then SL2 and SL3. Finally there is Inclusion one or I1 then I2 and I3. Another term Pique is the same as Inclusion so you may see P1, P2 and P3.  instead of I1, I2 or I3. As you would expect as you move down the scale from IF to I3 or P3 the marks become more prominent. A novice is often unable to see a VVS1 or VVS2 or even a VS1 mark in a diamond even with the use of the standard 10x  loop. One can not see a mark with the naked eye until it gets down to the  I1, ( P1), level ans even then it is difficult.  I3 diamonds are very heavily marked and can be seen easily with the naked eye. When checking the clarity the diamond needs to be very clean, otherwise it can be difficult, especially for a novice, to pick a permanent mark from a speck of dust.

5. Fluorescence – many diamonds ehibit a glow, understandably this is easier seen in the dark. This glow or fluorescence is similar to the way some thing’s glow under a black light eg a disco light. The colour of the glow is usually in shades of cream yellow or blue. Fluorescence can vary from None or Inert to Faint, Very Slight, Slight, Moderate, Strong, Intense, Very Intense, to Over Blue. Fluorescence is not considered favourable because it can mask the true colour of a diamond and if very strong can create a vague misty look to the diamond.

In general, when buying a diamond one needs to carefully consider these five quality criteria. As with most things it is usually best to buy good quality where possible however most people will have to make a compromise in line with their budget. As this post is offered as a practical guide to diamond buying here is my opinion about the order of priority that one should place on the grading criteria.
1. First you should consider the shape you would like.
2. Next one should consider the size.
3. Then the quality of the cutting.
4. Then the colour.
5. Next the clarity.
6. And last the fluorescence.
Having said that, once you have decided on the shape and size you would like, it would be a mistake not to not buy a diamond with a consistant quality level of cut, colour, clarity and fluorescence. For example it would be a mistake to buy a well cut diamond of good colour and clarity but with very intense fluorescence.
If you want to go for size a “show for dough” diamond, that’s fine; get the bigger size you want and sacrifice the quality but try not to buy a diamond where one or two of the qualities are way below the others.


A couple of final points first:-  Diamonds are the hardest natural substance known however there is a difference between hardness and toughness. You cannot scratch a diamond but you can break or chip a diamond. In my time I have seen many a chipped diamond, I wonder how many are chipped whilst washing under a metal tap ? So be aware while diamonds are tough if you are unlucky they can be chipped.
Second, most people spend a lot of time considering the quality of a diamond before buying. However once bought they tend to forget that those qualities soon lose their “fire” if the diamond is not kept clean. While the top is easy to keep clean, it’s the underneath, where the setting metal is, that can quickly collect a greasy film. This film will dull the look and colour of your diamond which effectly wipes out the quality attributes you paid a lot of money for. Fortunately the problem is easily fixed, warm water, some detergent and a toothbrush is all you need to clean away the film; be careful not to pull on the setting with the toothbrush bristles.

To finish, if you want to buy an all round very good quality diamond the starting point in my opinion is, Cut – ex, ex, ex, Colour – G, Clarity – VS1, Fluorescence – none. From this point you can improve the colour >F>E>D and or clarity VVS2> VVS1>IF to move closer to perfection but diamonds starting at this quality are expensive.
Assuming you have a budget, quality is always a trade off against the most immediately identifiable characteristic of any diamond, its size. As I have said size verses quality is a trade off and there is nothing wrong with dropping the quality so you can have a bigger size.

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This practicle guide is the opinion of the author, Gary Draper. Gary is a qualified, geologist, gemologist, diamond and gem grader, diamond and jewellery valuer and ex-lecturer in gemology with many years experience in the precious jewellery business in Sydney and London.

As always your opinion and comments are most welcome.

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Silver Gold and Metals in Tribal Jewellery

When discussing silver gold and metals in tribal jewellery, or any jewellery piece, perhaps the first point to make is that rarely is there just one pure metal. The metal is usually an alloy, which is a combination of several metals. For example if the metal is silver this usually means it is made from a combination of silver with smaller amounts of copper and nickle. Generally tribal jewellery is made with “white metal” which has a silver content that can vary massively. Rare collectable pieces can be valuable even when made form white metal with no silver content. However generally the better quality pieces are made with a high silver content. This is often as high 80% silver, sometimes stamped as “800,” or as high or higher than 92.5% silver which is Sterling grade, (the Britsh stanndard),  silver and is usually stamped “925”

With a few exceptions gold is not prominent in historical tribal jewellery and was not considered as valuable as silver. Understandably in more recent times with gold holding such a high worldwide value it has become a dominate store of wealth, especially among more affluent city dwelling ethnic groups. India is the world’s  biggest comsumer of gold for this reason.

Understandably it is important that one is able to establish the precious metal content of a piece before purchasing it. While the price of a piece will be influenced  by many factors such as age, rarity, quality, complexity in making, gem content, attractiveness and wearability the precious metal content is also important. As I have said better quality pieces are usually made with a high silver content and while there are plenty of genuine good quality non silver pieces on the market a buyer needs to be aware that there is also an abundance of super cheap, mass produced base metal copies which are simply not authentic tribal jewellery.
Most people know that gold is referred to as 9 or 10 carat, 14 carat, 18 carat and 24 carat gold. When discussing gold the word carat refers to the purity or the amount of gold in the metal. However when discussing diamonds and other gemstones a carat refers to the weight of the gem, 5 carats = 1gram.  24 carat gold is pure gold, therefore 9 carat gold is 9 parts out of 24  or 9 /24 or if divided down 3/8. So 9 carat, (9ct),  gold metal has a gold content of only three eights or less than half.  Instead of the stamp 9ct you will often see the stamp 375 which refers to the fact that the metal is 375 parts gold per 1,000 parts of total metal, i.e. 375/100o which is the same as 3/8.  Similarly 14ct gold is 14 parts gold out of a possible 24, so a little over a half is gold, it is also denoted by the stamp 583.5.  18ct gold is 18/24 or 3/4, so 18ct gold is three quarters pure gold or 75% and is often identified with the stamp 750.

Unlike gold, silver purity / content is not identified by carats, it is identified as parts per thousand. The most common purity term for silver, recognised world wide, is the British standard known as Sterling silver, it is recognised by the stamp 925. This is because the metal is 925 parts per thousand pure silver, or if you like, 92.5% pure silver. It is not common to find a stamp on silver metal which is less than 92.5% silver however the 800 stamp (80% pure silver) is the next most common. A wording of warning, just because a piece is stamped it does not mean that the stamp is accurate. However in my experience it usually is. The opposite is also true, in fact most pieces of tribal jewellery are not stamped, however they may still be made from 80% or more pure silver.

Much tribal jewellery is made from old pieces of jewellery or old coins melted down. The 18th Century Austrian coin the Maria Theresa Thaler, is well known for being used for this purpose, especially throughout the Maghreb (North Africa).  In 1857 the Emperor of Austria declared the Maria Theresa Thaler, (MTT) to be official coinage for trade. It then soon lost its status as currency for Austria and became a currency for world trade, (similar to the US$ today), and mints outside Austria began producing it. In all some 389 million MTT were minted between 1752 and 2000. The MTT was 83.3% pure silver. As a consequence much older tribal jewellery contains around 80% pure silver.

Be wary of pieces described as German silver, native silver, tribal silver, nickel silver, alpaca silver and other such names. These names are deceptive because usually the pieces actually contain no silver. The pieces are made from “white metal”  For example German silver typically consists of 60% copper, 20% nickel and 20% zinc

You may also come across terms such as gold or silver plated, gold leaf, silver gilt and gold or silver wash. If these terms are being used accurately gold or silver plated refers to a thin layer of gold or silver adhered to a base metal. Gold leaf is a thinner layer of gold on base metal while silver gilt refers to a thin layer of gold adhered to sterling (925) silver. Gold or silver wash refers to a very thin cover of silver or gold adhered to silver or base metal.

Your comments and or questions are most welcome.

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