What should I look for when buying a diamond?
Unless you are after a fancy coloured diamond, whiteness of colour and intensity of sparkle are key. You should also look for a reputable jeweller because of the following:
- imperfections are often hidden by the settings
- there are treatments which improve the colour or clarity of a diamond, most of which are only temporary
- there are synthetic materials which imitate diamond quite well and will often fool the less professional jeweller.
What should I look for when buying jewellery?
Jewellery should be closely examined before purchasing. What may look good in a jeweller's window may not be of sound construction and could therefore be a waste of your money. Design is becoming more and more relevant in the appeal of jewellery. But don't let design draw you away from the quality and practicality issues.
What should I look for when buying antique jewellery and silver?
To help you buy with confidence, your jeweller must have an understanding of the jewellery of the period in question. Condition is a consideration of utmost importance. We take great care in our purchasing to avoid pieces which have been the subject of inappropriate repair work and pieces showing significant signs of wear.
Being members of the British Antique Dealers Association we are particularly well qualified to give advice to the collector.
How should I clean and care for my jewellery and silver?
The method of cleaning required depends on the nature of the article, and particular care should be taken over period items.
We sell a range of cleaning materials and suggest that you contact us or call to see us to discuss your particular requirements.
Does all jewellery need to be hallmarked?
Much jewellery produced before 1975 did not have to be hallmarked. However, for an unhallmarked item to be described, for example, as 18-carat gold, it must still be up to the correct standard. This is an additional reason why it is important to buy secondhand and antique jewellery from a reputable jeweller.
Under the current law new items are exempt from hallmarking if they weigh less than: 1.00gms for all standards of gold, and 7.8gms for all standards of silver.
How do I know that I am viewing a fine quality diamond?
In order to give you complete confidence in buying your diamond from Barbara Cattle, we provide an idependent diamond report from internationally respected gemmological laboratories with all new diamonds weighing 0.50 carats and over. Our expert staff will be happy to guide you through the report an answer any queries.
Is provenance/maker important?
It is nice to buy items that have a provenance or are manufactured by a recognised and perhaps sought after craftsmen. We do though take the view that the condition and style of piece are more important criteria than maker/provenance.
I am thinking of starting a collection, what should I collect?
There are so many different ways of approaching this. Does one collect by type of article, by period, by assay office, by maker or simply just collect what appeals?
Ideally, one should collect something that has a degree of rarity without being impossible to locate. Regardless of the nature of what is collected condition should continue to be of foremost importance.
With our in-depth knowledge of the market along with our disinterested advice, we are perfectly positioned to assist both the established collector and those who have an interest in starting a collection.
Glossary
Baguette
A step cut in the shape of a small rectangular stone which may be tapered at one end.
Carat Weight
The standard unit of weight for diamonds and most other gems. One metric carat equals 0.200 gram. If all other factors are equal, the more a stone weighs, the more valuable it will be.
Clarity
Clarity is a diamond's relative position on a scale ranging from 'flawless' to 'imperfect'. Characteristics of clarity are classified as inclusions (internal) or blemishes (external).
The clarity grade is determined by the size, number, position, nature, and colour or relief of characteristics. When all other factors are equal, flawless stones are the most valuable.
Clarity Enhanced Diamonds
Diamonds which have fractures or large inclusions can be improved by having these features disguised or removed. These are called "clarity enhanced diamonds" and should be disclosed as such when being sold. The main methods of clarity enhancement are Fracture Filling and Lasering, which are described under separate headings.
Colour
Grading colour in the normal range involves deciding how closely a diamond's body colour approaches colourlessness. Most diamonds have at least a trace of yellow or brown body colour. With the exception of some natural fancy colours, the colourless grade is the most valuable.
Crown
This is the upper part of the diamond above the girdle and consists of a large flat area on top, known as a table, plus several facets below it.
Cut
Also known as the 'make', the cut represents the proportions and finish of a polished diamond. Cut can also mean shape, as in emerald cut or marquise cut. The cut affects both the weight yield from rough and the optical efficiency of the polished diamond. The more successful the cutter is in balancing these considerations, the more valuable the diamond.
Emerald cut
A step cut, usually rectangular, with cut corners.
This is a cut which accentuates colour and clarity rather than aiming to maximise sparkle.
Facet
A facet is a plane, polished surface of a diamond....
Fancy Diamond
A fancy diamond is one with an attractive natural body colour other than light yellow or light brown. Red, blue and pink diamonds are examples.
Flaw
An imperfection in a diamond.
Fracture
A crack inside a diamond, sometimes coming to the surface.
Fracture filled diamonds
When a diamond has a fracture that comes to the surface, it can be improved by a process known as "fracture filling". A liquid of high refractive index is forced under temperature and pressure into the fracture plane and the fracture is disguised but not altogether hidden. The glassiness of the filling causes a purple colouring to be exhibited when viewed at certain angles, something never present in natural diamonds.
When a fracture filled diamond is offered for sale, it should be disclosed as clarity enhanced.
Girdle
The girdle is the outer edge or the widest part of the diamond that forms a band around the stone.
Hardness
Hardness refers to a mineral's resistance to scratching on a smooth surface. The Mohs scale of relative hardness consists of 10 minerals, each scratching all those below it in the scale and being scratched by all those above it.
The scale is an arbitrary one. The hardness of diamond is 10, followed by ruby and sapphire at 9, followed by topaz at 8. However, diamond is approximately 140 times harder than ruby and sapphire which in turn are approximately 5 times harder than topaz.
Inclusion
An imperfection internal to the Diamond.
Internal Graining
Internal indiciations of irregular crystal growth. They may appear milky, like faint lines or streaks, or may be colored or reflective.
Irradiated diamond
A diamond that has been exposed to radiation in order to improve either its colour or clarity. An irradiated diamond
should be disclosed as such if offered for sale.
Lasering
Any large unsightly inclusions in a diamond can be effectively removed by a process known as lasering. A lasered diamond can be detected since the "drill hole" from the surface of the diamond to where the inclusion was is often visible under a lens and looks like a small tube.
When a lasered diamond is offered for sale it should be disclosed as 'clarity enhanced'.
Loupe
A magnifying glass usually of 10X magnification.
Melee
Small Diamonds under .20 carat.
Mohs scale
This is the ten point scale of mineral hardness keyed to the following minerals:
- Talc
- Gypsum
- Calcite
- Fluorite
- Apatite
- Orthoclase (feldspar)
- Quartz (citrine and amethyst)
- Topaz
- Corundum (ruby and sapphire)
- Diamond
This scale is neither linear nor in a particular ratio. Diamond is approximately 140 times harder than corundum which is approximately 5 times harder than topaz.
Pavilion
The pavilion is the bottom part of the Diamond, below the girdle.
Round Brilliant cut
This is the most common cut applied to a diamond and comprises 58 facets. It is the cut which makes the most efficient use of light to maximise brilliance (sparkle) and dispersion (fire).
Spread stone
A diamond with a large table and a thin crown height. Such a diamond will appear large but lack sparkle.
Treated Diamond
A diamond whose body colour has been induced by some form of artificial irradiation. This is often done in conjunction with controlled heating, a process known as annealing.
