Dealing With An Expert

Mining Throughout The World

Natural coloured diamonds are found in several locations throughout the world. These rare gems are created through extreme conditions over millions of years. Although natural coloured diamonds are found around the world, there are only a small number of mines that are currently mining for them because of their rarity. In fact, in the past 20 years, there have not been any new mine openings. The largest natural coloured diamond mine the Argyle Mine in Australia just announced that by 2020, they will be closing due to a depleting supply of diamonds.


The Laboratory Gemmologist

The laboratory gemmologist will have extensive knowledge and training when dealing with natural coloured diamonds. They understand the physical properties of natural coloured diamonds, study the minerology, geology and gemmology and are highly trained to certify natural coloured diamonds. They study the gem and understand and recommend how to improve the appearance, consistency and durability of the stone. There are gemmologists who can even tell you the origin of the gem. The laboratory gemmologist is instrumental in developing tools and techniques to detect any artificially coloured diamonds that appear in the marketplace.

Criteria Used in Assessing Gemstones

Refractive Index

Each type of diamond or gemstone refracts light in a very specific way. This can be used to establish the type of gemstone.


Studies how diamonds and other gemstones absorb and disperse light, which will determine the quality in colour and clarity. This helps to identify defects in the diamond, and can also spot natural from man made diamonds.

Relative Density or Specific Gravity

Measures the density of a diamond or gemstone. Each type of diamond or gemstone will respond a certain way when weighed in both traditional scales and in water. This density is another important tool in determining the type of gemstone. Diamonds have a density of 3.5-3.53.

The Lapidist Or Gemstone Cutter

The lapidist is highly skilled in understanding the properties of the gemstones, and are trained on how to enhance the appearance and durability of the stone. They look at fractures and inclusions and study the stone before cutting and polishing the stone.

Rich History of Diamond and Gemstone Cutting

Mother nature produced these beautiful naturally coloured diamonds and gemstones, but it is man who has learned to enhance the beauty to perfection. The art of the gemstone cutter is one of skill, practice and intuition. Early techniques would see a diamond and gemstone cutter remove up to half the original carat of a gem. The technology has come a long way from the humble beginnings of cutting, and today’s gemstone cutter blends science and art to enhance every gem. A cutter has extensive knowledge on the properties of diamonds and gems and studies the gem closely to enhance any advantages a stone has such as colour and clarity, while working around disadvantages of a stone such as inclusions or fractures. These highly trained artisans know how to bring out the natural aesthetic of natures beauty

Early Styles of Diamond and Gemstone Cutting

One of the earliest cut techniques that lapidists used was known as a cabochon cut. Lapidists would create a flat or very slightly concave bottom, with a dome style on the top to let in light. It was quite easy to achieve by rubbing and polishing the gem, and did not need complicated tools or techniques to achieve. Up until the 14 century, the majority of diamonds and gemstones used this technique. Over time, the technique became more sophisticated and ladipists now use cutting in two styles; intaglio and reverse intaglio, where there is a smooth cameo on the gem. Today, you can still see the cabochon cut used although it is not a popular cut for diamonds. Natural coloured diamonds and gemstones form in nature with natural facets. Lapidists work with these facets to achieve truly beautiful gems. As cutting techniques advanced, craftsmen began enhance naturally desired properties of the crystals such as symmetrical proportions to capture and create the greatest brilliance. Symmetry continues to be an important aspect of gem cutting, as even today’s most complex cuts utilize the same group of geometric structures as their basis. Today, the most common shape for diamonds is called the Round Brilliant. This popular style, which usually consist of 58 cuts has been a favourite for engagement rings, and is known to bring ‘fire’ to the diamond. Other popular cuts are a square Princess, a tear dropped Pear, Oval and a rectangular Emerald cut.

The Stages a Stone Goes Through:

The Jewellery Designer, Jeweller And ManuFacturer

Jewellery designers require knowledge and some gemology training to understand the material they are designing and working with. They will have knowledge of the value of the materials, what materials can be used together, the process the gemstones undergo from the jeweler and what could damage the gemstones. Jewellers require an understanding in gemmology so that they understand what quality and value of gem they are working with. They are artisans who understand the nature and properties of diamonds and gemstones along with other materials used such as silver and gold. After purchasing a naturally coloured diamond or gemstone, Benchmark Conversion will help you at every step to turn your treasure into a custom designed piece that will maximize its value as an asset while still being enjoyed. Benchmark Conversion assures that high quality production standards are met and that every piece produced is certified as to content.


It is important when you purchase a naturally coloured diamond or gemstone to always have reputable third party certification. At Benchmark Conversion, we pride ourselves in always providing thorough third part certification for all our naturally coloured diamonds and gemstones. To accomplish this we work exclusively with GIA, the Gemological Institute of America.