The practice of over grading the diamond to increase the perceived value. This practice is illegal. See link for more information. Rapaport.
Over graded diamonds
De Beers Forevermark
De Beers Forevermark diamonds with the unique serial number and logo.
Diamond cleaning
Because your diamond when worn naturally attracts grease or oil, they will need periodic cleaning.
Even when touching a diamond with your fingers natural oils from your skin will change the brilliance of your diamond, making your diamond lose its lustre or brilliance.
A simple way to keep your diamond jewellery looking beautiful is a weekly bath in a household cleaning solution. A simple window cleaner will work. But make sure you give it a thorough rinsing followed by a very light brushing using an old tooth brush to remove the oils and cleaning liquid.
Pay special attention to the underside of the ring and bottom of the stone, as this is where most of the oils or hand creams accumulate.
Make sure when using a brush not to apply to much pressure especially if the jewellery is old or fragile. This is a good time to check the diamonds are tightly set and none are missing.
Never use Chlorine, bleaches or abrasives when cleaning diamonds set in jewellery. This will remove the rhodium plating on white gold and could leave scratches which will attract even more dirt.
If the ring has fine claws or filigree work an ultrasonic cleaner is necessary to remove deep encrusted dirt behind the diamonds. High frequency sound waves and jewellery detergent fluid will remove hard to get to dirt and grime. Make sure this is done by a professional to avoid damage or loss of stones.
Brown Diamond
In natural diamond the colour is related to a lattice imperfection. This can be mimicked in synthetic or treated diamond by a variety of treatments including annealing, heating or irradiating. The heat and pressure or irradiation can result in the lattice deviation resulting in the brown or pink colour.
Orange Diamond
The ultimate colour for the collector, Orange is extremely rare in diamond. To be certified fancy orange colour, there cannot be any brown in the stone.
Seal
Plastic covering that provides a safeguard against loose diamonds being lost or damaged. Laboratory sealing has a number of security features including electrostatic security bars, pressure-sensitive transparent adhesive and cryptoprint text which only becomes visible after opening the seal.
Polish Lines
Lines left on the surface of the diamond which are visible under magnification, normally removed during the final diamond polishing process. Polish lines can affect the polish grade of the diamond.
Internal Laser Drilling
Treatment to enhance the apparent clarity of a diamond by reducing the visibility of dark inclusions. A precise laser beam is focused on a small dark inclusion – the black in the inclusion dissipates from the laser beam itself. Click here to learn more about laser drilling and clarity enhancement.
National Diamond Colour Master Set
Set of certified and registered diamonds, with known colours from which other master sets may be derived.
Diameter
Diameter is a reference measurement against which most of the proportions on a diamond are calculated. On a round brilliant cut diamond, this is the length in millimeters of a straight line going through the center of a diamond. Click here to learn which standard diameter measurements correspond to specific well-proportioned carat weights. On a fancy shaped diamond, this is the average measurement in millimeters of the length and width.