The term precious and semi-precious applies to gemstones that have certain characteristics. They are the four C’s, that stand for Colour, Clarity, Cut and Carat. Buying a gemstone can be a daunting task if you are not informed about what you should look out for. Follow our simple guide for buying precious and semi-precious gemstones.

The first C in the list is colour and this is perhaps the most important factor in determining the cost of the gemstone. In fact, the colour of a gemstone can make up 50 to 70% of its value. When buying your gemstone it is always best to opt for a stone that is bright and intense with a vivid colour. Of course, a factor in how your gemstone looks is the light that you are viewing it under. Precious stones will vary when viewed under natural light throughout the day and they will also be different under artificial light. This is especially true as incandescent light enhances red stones, while fluorescent light brings out green and blue colours. In general your stone should not be too light or too dark in colour.

The second characteristic to be aware of is clarity. This refers to the transparency of the
stone. Gemstones will never match the clarity of diamonds but clarity and colour combined should be your first priority. Some of the gemstones for sale will be clear and bright, while some may have inclusions. These are tiny “flaws” within the stone and are expected in precious stones such as sapphires and rubies. In some cases these inclusions can actually enhance the value of the stone and this is especially true of star sapphires.

The way the precious stone is cut can also add or detract from its overall value. The shape of the stone is achieved by cutting the surface into a number of small faces or facets. Stones can also be carved to produce a 3-D effect. If you are buying a diamond, an ideal cut is the best shape to opt for. This cut maximises the amount of light reflected into and out of the stone to maximise its brilliance.

The final C to be aware of is carat. This refers to the weight of the precious stone and contributes to its value. A carat is equivalent to one fifth of a gram and there are five carats to every gram. It is important to bear in mind that carat weight bears no relationship to the size of the stone. Always make sure when purchasing semi-precious or precious to go to a reputable dealer.