CUT – one of the 4Cs of Gemstones
The 4Cs of Gemstones describe the cut, colour, clarity and carat weight of a stone,
each of these four categories defining the stone and assessing its value. This system, developed by the Gemological Institute of America in the 1940s – 1950s, is well-defined for diamonds; however, although used for other gemstones, it is not accepted universally, as gemstone 4Cs have different implications. We will explore gemstones cuts, what these mean for the beauty and the value of the stone and how to go about choosing the correct cut.
The Purpose and Shape of a Gemstone’s CUT
Gemstones are found in various colours, many of which are truly spectacular. In order to preserve the intense colour, it is imperative that these gemstones are cut with particular care and that the correct cut is chosen for each stone.
The cut displays the gem’s beauty and depth of colour, its shape and its faceting style. Stone size, colour, inclusions and clarity all have to be taken into consideration by the cutter in order to provide the gemstone with its best symmetry and proportion dimensions. The most relevant objectives would be a pleasing symmetry and well-defined facets junctions, light reflection, and smooth, flawless polishing.
Gemstone cutters strive to preserve and enhance colour, maintain size and maximum carat weight, and reduce inclusions to improve the stone’s clarity, in order to yield the best symmetry and proportion in a high quality cut. All of these considerations will affect the value of each stone, so when purchasing a stone ensure that the cut quality is the first priority.
Examples of cuts and colours of Tourmaline
Flawless coloured gemstones are more rare than flawless diamonds and clarity is not as important as that in diamonds. An example is with emeralds – the natural process in the formation of emeralds is a violent one, which results in natural flaws found in even the most valuable emeralds. The darker the colour of gemstones, the easier it is to hide flaws. Generally, these flaws do not affect the stone’s value.
The external structure of a gemstone is similar to that of a diamond. At the centre of the stone’s surface is the table, the whole top part is the crown, the girdle is the top third of the stone’s body or pavilion and the culet is the lowest part of the stone.
The cut affects the final shape of the stone.
The market standard cut for rubies and sapphires is the mixed cut (brilliant crown and step pavilion) while the step cut is more usual for emeralds.
The girdle outline defines the shape of which there are many choices such as the more common oval and cushion shapes to the more rare emerald and round shapes. The shape generally relates to the original rough shape.[/et_pb_text][/et_pb_column_inner][/et_pb_row_inner][/et_pb_column][et_pb_column type=”1_4″][et_pb_text admin_label=”Text” background_layout=”dark” text_orientation=”left” header_font=”Roboto||||” text_font=”Roboto||||” text_font_size=”12″ background_color=”#3b341a” use_border_color=”off” border_style=”solid” custom_padding=”5px||5px|” disabled=”off” border_color=”#ffffff”]