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Does it have to be a diamond…?

Whilst there are many different colours of diamonds (which we’ll come onto in a different post) we’re going to look specifically at alternatives to the colourless diamond.  Common replicas include Cubic Zirconia, Moissanite, Petalite, Zircon and Topaz.  For even cheaper prices clear glass or acrylic is often used in high street jewellery.  These can all be found in incredibly clear and brilliant examples, they’re cheaper, many look similar, so how can you tell what is real?  Take the well known crystal brand Swarovski, this beautiful necklace (below) is stunning in many different lights, can you really tell that it’s not diamond; Wedding necklace and if you can does it matter?  In the cases of white Zircon, Topaz and Petalite, among others, you’re still getting a real gemstone, similar mining processes and cutting, but paying nowhere near the price of a diamond.  In any event to be fair can anyone really tell whether the rock around your neck is actually synthetic crystal or diamond anyway. Disadvantages of the alternatives So the obvious disadvantage of anything that isn’t diamond or one of the other really desirable gems is that it is likely to lose value, a real diamond is more likely (but not guaranteed) to gain in value over time, particularly good quality gems which are well looked after.  However, turning this on its head of course you probably won’t have paid anywhere near as much for a moissanite or CZ so does it really matter, to each their own. The other obvious disadvantage is that unless you’re wearing a diamond you are not wearing one of the hardest gems known to man…this could make your item easier to scratch or damage…you might not be able to use it to carve your name onto furniture… On a serious note each gem (real or synthetic) has different refractive/fluorescence and brilliance or sparkle.  This is where the real trick lies in trying to distinguish real from fake but in reality without close examination it’s unlikely that even an accredited jewellery professional is going to argue if you tell them your CZ is a diamond. There are also advantages to none diamond pieces, unless you’re particularly precious about your precious gems, synthetic or less pricy gems means you can afford either bigger pieces, or more items than you might be able to with real diamonds.  They can look just as stunning (I wore CZ on my wedding day so no arguments please, but cue an opportunity to flash some wedding bling!) Wedding bracelet and chances are most people you pass in the street won’t be able to tell.  After all how many of us have spent our journey to work staring at someone’s engagement ring wondering whether that giant rock is real or not…?! Ooh more importantly this means it’s more difficult to tell if that rock he got for you is real…hmmm that’s when it’s good to know a gemologist 😉

Now for the science bit…

Diamond in tweezers

 

Diamond is a mineral that is a crystalline form of carbon, the element ‘C’. It shares its chemical formula with graphite ‘C’. However, the carbon atoms in graphite are arranged in layers, and have weak bonds between the layers, making it soft and slippery. The carbon atoms in diamonds are arranged in tight 3D patterns with strong bonds in all directions which gives diamond its characteristic hardness.

Diamonds form between 90 and 120 miles under the surface of the earth, far our of reach of mining and they may remain there below the earth for millions and even billions of years until conditions within the earth’s mantle lead to violent eruptions that blast the already-formed diamonds and magma rapidly to the surface of the earth.  Some of these diamonds will be erupted, but others get stuck in the track of the eruption leaving conduits called pipes. This is where they may stay, fully formed, for millions more years until they are discovered and mined.  It’s these pipes which form the seams which are mined for diamonds and are much closer to the surface, although still a staggering depth of up to around 2 miles into the earth.

Often erosion of the Earth containing these pipes occurs which can carry diamonds into neighbouring rivers and streams, and even the ocean.  As the diamonds are heavy they stick to the bottom and are caught in small whirlpools. Deposits in rivers and streams are called alluvial deposits and they often contain higher quality diamonds than primary deposits mined from pipes because only the better specimens survive the pressures forced upon it with the water’s crashing actions against the rocks. Such deposits for example along the Namibian coast, contain in their yield about 95% gem quality diamonds.

 

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All the “C”s

So whilst it’s lovely to gaze over diamonds and dream, what happens when you want to purchase?  It’s pretty well known that the things to look for in a diamond are the C’s i.e. colour, clarity, carat weight and cut, but what does this mean in reality and is this really all there is to it? 

Diamond grading

 

Colour

Basically the less colour visible the higher the price (except for fancy coloured stones, but again more on coloured diamonds later).  You will mostly come across the GIA grading system which uses a letter system of colour grading. D being the highest grading of colourless, descending towards Z travelling through near colourless, faint yellow, light yellow and so on.  At the very basic level as the colour and grade increases the price of your stone decreases.

 

Black diamond

Clarity

Clarity is defined as the degree to which a stone is free from external marks (called blemishes) and internal features (called inclusions). Like with colour the freer the stone is from blemishes and inclusions the more expensive the price tends to be. These factors, like with colour, are given grades; the GIA clarity grades start at F1 “flawless, no blemishes or inclusions” which are very rare and expensive (essentially, “we wish”).  Diamonds are generally found in high street jewellery around lower grades such as SI1 & SI2 which are slightly included, ranging from easy to see under 10x magnification (i.e. using your loupe) and somewhat easy to see with your naked eye. Diamond grades end at I1-I3 (P1 -P3 is used in some countries) which are imperfect, characteristics and flaws which can be seen easily with the naked eye.

 

D grade diamond ring

Carat

The unit of weight used for diamonds is the carat, in most cases the higher the carat weight the higher the price, a carat is a unit of weight equalling 1/5 of a gram. The weight of small diamonds are often expressed in points, with one point equalling 0.01 ct (carat) Diamond jewellery in stores may often have the total diamond weight on display which for example 1ct for a 5 stone ring will not therefore be of an equivalent value as a 1ct single stone in a ring. Also take note if the quantity is expressed in points or carats, as 0.25 points is not equivalent to 0.25 ct which is a quarter of a carat.

Cut

This refers to the proportions and finish of the stone, two of the main considerations of cut are:

  • Do you see brilliance all across the stone when you look through the stone face up? You should not see large dark areas.
  • Are you paying for excess weight? is the stone too fat basically when you look at it sideways a poorly cut stone may have a very thick appearance from the side but look much smaller from the top this will also effect the brilliance that stones gives off. Symmetry is also a consideration as this also affects the level of brilliance emitted by the stone.

Cut can be judged by the naked eye and a 10-power magnifier, but it is not as simple as it sounds (naturally!)  Cut should be considered in more detail, looking at the cutting style and quality and the shape of the stone.  The finish is also important as how well the cut is finished can affect sparkle and brilliance.

Whilst cut is very much about personal taste trends affect prices so at the moment round stones tend to cost more than pear, marquise and emerald cuts but this hasn’t always been the case.

Normally square shapes cost less than round as there is less wastage when the stone is being cut from its rough state, and there is usually less demand for squares. However, depending on demand in different areas of the world princess cuts (squares) have occasionally sold for more than rounds.

 

Heart facet

Anything else…?

Well in short…yes!  (Sorry this is turning into a long post but we promise this is only scratching the surface, hard to do on a diamond!)  Transparency is another factor to consider, the degree to which the stone is clear, hazy or cloudy as again this will alter how the stone reacts to light and therefore how it looks when being worn.

The other thing to take care of when dealing with diamonds is the treatment status i.e. whether the stone has had any external treatment since being mined.  There are a number of techniques and treatments which have been developed to improve the look of white diamonds; some have been deliberate attempts to deceive buyers but with a reputable jeweller you should be able to ask about any treatments of the stone.  An example is the process of using a laser to vaporize black inclusions, this leaves a fine white thread that starts at the surface and travels into the stone.  This treatment is permitted but must be disclosed on any certificate obtained.  Fractures and cracks can be filled with a glasslike substance that is visible only under magnification.  Certain types of yellow-tinted diamonds are put through a high-temperature, high-pressure treatment (HPHT) process to make them colourless. This treatment is permanent and heat treated diamonds can only be identified in a lab.

Depending on what you’re after in a gem treatments are not necessarily something to shy away from, they can reduce the value of a stone but give you the look of a much better quality stone.  One of the things you should beware of though when it comes to treatments (not only in diamonds) is that not all treatments are permanent, the filler we have mentioned above is not a permanent treatment and bad care or handling can loosen the filler or change its colour.

 

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Are diamonds really a girl’s best friend…?

In the next few posts we’re going to take a closer look at diamonds.

Diamond in tweezers

 

Diamonds are notorious for their desirability and associated price tag, they are apparently a girl’s best friend, forever and a long standing essential in engagement rings.  Depending upon where you read the name comes from “Adamas” the ancient Greek word for “unconquerable” but other sources cite the name as meaning “indestructible.”  Either way because of its durability the diamond has been revered as far back as 800 B.C. in India which was the first major source of diamond and it’s easy to see why when you find out that they are the hardest natural substance found on Earth (10 on the mohs scale), impermeable to acids or solvents, with a melting point of an unimaginable (to my mind) 3547’C!

One of the more surprising facts about diamonds to my mind is the fact that whilst our high street and designer jewellers would be bereft without their bevy of brilliant cut beauties, the majority of mined, natural diamonds don’t actually get made into jewellery.

So what makes diamonds so desirable?  Of course, like most gemstones, they are rare, having been made over a billion years ago.  They are expensive to mine, it’s said that to produce one carat of diamond around 250 tons of earth will be mined.   They are expensive to facet, with around 50% of the original weight being lost during preparation.

Uncut diamonds were worn as talismans for protection in battle and to ward off illness, floods, thieves, evil spirits and even snakes, so depending upon your superstitious nature there may be nothing else that will do!

 

Picture from Wikipedia “Diamond”