Measure of resistance to scratching and abrasion. Diamond is the hardest material on earth, a 10 on Moh’s Scale; however, it is not the toughest. Hardness and toughness together determine the durability of diamond.
Diamond cut or shaped into a heart, with a cleft in the wide end, and a softly tapered point at the narrow end.
Hearts & Arrows
Describes a pattern that appears in some round brilliant cut and square cushion cut diamonds that have a certain parallelism and symmetry. When viewed from above through the crown, the pattern is a series of eight arrowheads. From below through the pavilion, the pattern appears as eight heart shapes. Hearts & arrows does not mean that a diamond is ideal cut, only that it is symmetrical.
Hot Laser Inscription
The use of a laser beam to write a number or customised personal message on the girdle of a diamond, generally for identification purposes. Hot laser machines operate at a higher wavelength, and unlike cold laser inscription can penetrate into and thus damage the diamond; penetration can result in chips and fractures. Click here to learn more about diamond laser inscription.
HPHT (High Pressure High Temperature) Treatment
Treatment to change or artificially enhance the colour of a diamond. Certain types of diamonds are subjected to extreme heat and pressure conditions in a laboratory, which rearranges their atomic structure and thus alters their colour. Click here to learn more about HPHT treated diamonds.
Occasionally ‘colourless’, or Cape Series diamonds will have a visible negative tint of brown or grey. These diamonds are graded on the same scale of color saturation as Cape Series diamonds, but will state the hue on the certificate. Diamonds with brown, grey, or ECG hue are of lower value than those with no hue. Click here to see where to find hue on a Diamond Certificate.
The diamond trading floor that gives all diamond buyers direct access to DCLA guaranteed diamonds from Australian diamond dealers.
Tuesday 25 April, 2017
CHRISTIE’S TO OFFER 92CT. PENDANT
A 92.15 carat diamond pendant worth up to $20 million will lead Christie’s Magnificent Jewels auction in Geneva next month.
Thursday 20 April, 2017
GRAFF UNVEILS 105-CARAT D-FLAWLESS DIAMOND
Graff Diamonds has unveiled the 105.07 carat D flawless pear shaped diamond, it has named the Graff Vendôme after its new retail outlet at Place Vendôme in Paris.
Monday 10 April, 2017
LETSENG MINE YIELDS 114CT. DIAMOND
Gem Diamonds has found a 114-carat rough diamond at its Letšeng mine in Lesotho, the miner reported Friday.
Tuesday 4 April, 2017
SOTHEBY'S SELLS 59.6 CARAT PINK FOR $94.2 MILLION AUD
Steinmetz Diamonds owned by Israeli billionaire Benny Steinmetz, spent two years cutting and polishing the Rough diamond. Which was mined by De Beers in Botswana, Southern Africa.
Thursday 30 March, 2017
DE BEERS, LUK FOOK TO CO-BRAND GRADING REPORTS
Tuesday 21 March, 2017
59.6 CARAT VIVID PINK DIAMOND
Sotheby's plans to auction the famous "Pink Star" diamond an internally flawless, fancy vivid pink stone at its sale in Hong Kong on April 4.
Wednesday 8 March, 2017
GIA FINDS SIGNIFICANT UNDISCLOSED SYNTHETICS
The Gemological Institute of America (GIA) recently uncovered an unusually large number of undisclosed synthetic diamonds mixed in with natural melee diamonds, the lab confirmed with Rapaport News on Monday.