• Testing & Identifying Diamonds

     One of the first steps when looking at any jewellery set with a gemstone is identification. Depending of what gemstone you are looking at will determine everything, from value to the way in which you can clean the jewellery it is set in.

     Certain gemstones have very specific characteristics which make them relatively easy to identify, for example, Lapis Lazuli has an opaque appearance with a deep blue colour and on most occasions you will notice the gold/yellow flecks of Pyrite in the composition. These traits make Lapis Lazuli relatively easy to identify, especially as there are not really any other semi-precious or precious gemstones which have all of these characteristics. 

     However, when we look at diamonds, it is not quite so straight-forward to determine if you are actually looking at a diamond. There are many intricate ways to help eliminate the possible options, such as looking at the way in which the stone has been cut, if the stone is a diamond it will likely not show much sign of wear, the edges (facets) of each side of the stone should appear sharp and precise with little or no abrasion. This is due to the hardness of diamond, it is so hard one of the only things which will abrade a diamond is another diamond!

     On a more scientific note, diamond is singularly refractive, so if you look through the side facets of the diamond you will see clearly the back facets of the stone. Whereas, if you are looking at a stone with double refraction, such as synthetic Moissanite, you will see the back facets are blurred and there appears to be 'double vision'. Therefore, if you see notice double refraction then you know it is not a diamond.

     Another simple trick is looking at the inclusions within the stone, there are some very popular simulants of diamonds which are man-made and therefore, have no inclusions. The vast majority of diamonds have inclusions, they are the diamonds natural hallmark, and unique to each stone. The inclusions are formed during the formation of the diamond in the Earth's core.When diamonds are graded their clarity is effected by the inclusions. Therefore, if you can see inclusions within the stone, that is a sign it could be a diamond. Please note, not all inclusions are visible to the naked eye and most require magnification to see.

     Now, one of the most well known ways to identify diamonds is using a diamond tester. Whilst every diamond specialist should not be without one, the tester is certainly a back up tool rather than the first thing we use. The diamond tester is more used to confirm our suspicions rather than the initial identification process. It is also worth remembering that certain stones will register as 'diamond' by the diamond tester when in fact they are not.

     Synthetic Moissanite is a perfect example. Synthetic Moissanite has become more popular in recent years as an alternative to diamond. As the name suggests it is a lab created stone and NOT natural. Some important traits of synthetic Moissanite are: it is doubly refractive, it generally has a darker/browner colour than diamonds. Approximately 30% of synthetic Moissanite has growth lines, these are the only type of inclusions, they are like pins through the stone and are completely straight. It will test as 'diamond' on a diamond tester, however, an experienced diamond specialist will be able to accurately identify it.  

     Whilst the above will hopefully help you better understand the identification process, if you are looking to identify a gemstone we always recommend taking your jewellery to your local reputable jeweller, ideally one with a gemmologist or diamond specialist within their team. We have both, a gemmologist and diamond specialist and we welcome our customers to pop in for us to take a look for you and help you identify your gemstones. 

     If you would like to take a further look in to diamonds, and what to consider when looking to purchase diamonds, please take a look at our blog.

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