Sometimes it’s not possible to find what you want among available gemstones. You may have a design in mind that requires a specific material or type of cut that is simply not available, or you might have sold a piece of jewelry that used a particular stone and want to repeat the design. Your only option then would be to have the stone cut to order.
Obviously, cuffing to order will be more expensive than buying a ready-cut stone, which may have been cut as part of a large consignment, possibly in the Far East. But don’t let that put you off. Having your stones cut to order is very satisfying for a designer, and perfectly achievable as long as you understand the parameters of what is possible.
GRADING ROUGH MATERIAL
Gemstone rough comes in a range of qualities and prices. The best material accounts for only 5 per cent of the total mined and will always be sold at high faceting prices. The grades of rough gem material are usually described as:
A+ Exceptional colour and clarity
A Top grade/clean
B Good/eye clean
C Medium/some inclusions
Getting stones cut to order
You’ll need to find yourself a knowledgeable dealer who can access the necessary rough material, has good lapidary contacts and is willing to listen to your ideas. Cutting and material costs will be priced per carat, not per piece. Generally, the larger the cutting order is, the better the value. Cabochons are a cheaper option as the rough material and cutting charges will be less. However, faceted gemstones can still be cost-effective, especially for a design that needs a large number of small stones of the same size in matching material.
Consider what type of material is suitable for your design. Hardness, cleavage and durability are important considerations and your first choice of material might not be the right one. Crystal shape, size and colour range will have to be taken into account; some gemstones only occur in small sizes, for example. You also need to think about design practicalities, such as the weight of the stones. Earrings, for example, should weigh no more than 7 grams or they become uncomfortable to wear. The different density of gemstones means that a certain size of turquoise stones might be suitable for earrings, while earrings using the same size of garnet, topaz or corundum may be unwearable.
Rough material can be very deceptive and may not give an indication of the stone’s final appearance. Fine planes of colour may be removed with just a small amount of grinding, resulting in a significant loss of colour intensity. To obtain a matching pair of stones, the lapidary might have to cut as many as five stones.
Certain gemstones are remarkable for their colour, size or properties and it may not be possible to find a similar stone quickly – or at all. Some stones become unavailable as the source is mined out.