Diamonds Diamonds Series Part 4: Diamond Colour by Val Baynton

For descriptive and for valuation purposes, diamond dealers Dresden Green was mounted to create an impressive hat ornament and is stored use what is known as ‘the 4Cs. These refer to cut, clarity, in the Green Vault at the Dresden Palace in Dresden, Germany. The Wittelsbach, colour and carat weight. In this final part of a series of four now called the Wittlesbach-Graff Diamond has recently, and controversially, articles examining the four Cs, Val Baynton looks at colour. been re-polished by its current owner Laurence Graff, and it has been on public Curiously, for diamonds the two extremes of colour, i.e. lack display alongside the in the Smithsonian. These diamonds are so of colour and intensity of colour, are both sought after by important because they provide a standard of an undisputedly naturally coloured diamond aficionados. gem, that more recently discovered coloured diamonds can be compared Many diamonds may appear colourless but, in fact, most against. Technology and science has developed so rapidly in recent years that it have a tint of yellow, and, since the mid 1950s, every is possible to manufacture coloured diamonds and for this reason it is important ‘colourless’ diamond has been graded against a colour scale to only buy stones that are properly certified. that was devised by the Gemological Institute of America Editor’s Note: The Hope diamond is only a small part of the original Tavernier (GIA). The scale was introduced to standardise the industry Blue. Its first known owner was the French gem merchant Jean Baptiste and because dealers were already using the letters of A, B and Tavernier. The histories of Tavernier’s journey’s suggest the gemstone origi- C, the scale begins at the letter D and progresses through the nated in India, in the Kollur mine in the of (at alphabet to Z. the time part of the Golconda kingdom), and was acquired in the seventeenth Diamonds graded D, E (both exceptional white) and F (rare century, before being sold to the ‘Sun King’, Louis XIV whence it became white), are the best quality, but the differences in tone between known as the French Blue. This fascinating story may be followed, from the the three categories are virtually impossible to distinguish seventeenth century to the Hope diamond on Wikipedia. except by experts. G (rare white) H, (white) I, or J grades (slightly tinted white), are still virtually colourless and so The definitive ‘C’ quality represent good value, especially if combined with good cut, Of the four Cs then, cut, colour, clarity or carat weight, which is the most clarity and/or carat weight. Grades K and L (tinted white) are important when buying a diamond? For me the cut is the clinching factor. The less good, whilst grades M to Z are referred to as ‘tinted diamond could be the most amazing carat size, but without the cut and the colour’, and the yellow shade is progressively more obvious, consummate skill of diamond cutters and jewellery makers in creating a even to the untrained eye. Diamonds can be graded by eye, but sparkling stone with perfect proportions to make the most of the individual and are more normally graded by examining clean stones through specific dimensions of the gem, the stone will be the poorer. Colour is clearly a their widest point and comparing them against a set of pre- vital factor and intensely coloured stones and pure colourless ones, are graded master stones. For colourless diamonds lack of colour incredibly desirable, but a diamond cutter is still needed to emphasise its is the prized quality and commands premium prices, whereas charms. Also, for most collectors, the prices of these incredibly rare stones are for coloured or fancy diamonds the opposite is true and the so high that consideration of purchase is not possible at all. Finally, clarity. more intense or vivid the shade, whether blue, yellow or pink, Inclusions are fascinating because they reveal so much about the way the stone the more the diamond is worth. has survived the incredible forces of nature but again an expert cutter is required Colour in diamonds is generally caused by impurities of to cut the stone in such a way that light is reflected to the very best, avoiding trace elements, which were present when the diamonds formed the inclusions and their potentially deadening effect on the reflection and millions of years ago deep below the earth’s surface. The most refraction of light through the stone. common impurity is nitrogen causing a yellow or even orange colour whilst boron results in a blue diamond. Other fancy The Colour Table diamonds can be green, caused by naturally occurring GIA - The Gemological Institute of America radiation reacting with the diamond over thousands of years, CIBJO - the World Jewellery Confederation whilst pink, purple or red diamonds develop as a result of a GIA UK Traditional CIBJO Comments defect or alteration in the atomic and internal structure of the stone whilst the diamond is being formed. Black diamonds are D Finest White Exceptional White + Colourless a result of numerous dark inclusions which prevent refraction E Finest White Finest White Virtually Colourless and dispersion of light and give the stones a dark appearance. Of all these shades blue, pink and yellow hues are generally F Fine White Rare White + Virtually Colourless considered to be the most desirable. G Fine White Rare White Virtually Colourless H White White Virtually Colourless Famous Coloured Diamonds. Coloured diamonds are much rarer than colourless ones and I Commercial White Slightly Tinted White Very Faint Colour large ones rarer still, so unsurprisingly there are several J Top Silver Cape Slightly Tinted White Very Faint Colour legendary stones that have interesting and often mysterious histories. Amongst the blue diamonds are the 45.52 carat Hope K TSC to Silver Cape Tinted White Faint Colour and the 35.56 carat Wittelsbach diamonds, whilst pink ones L Silver Cape Tinted White Faint Colour include La Grand Condé at 9.1 carats and amongst the green M Light Cape Tinted Colour increases with Grade varieties, the Dresden Green at 41 carats is an exceptional stone. All these legendary diamonds have had several, mainly N Light Cape Tinted Colour increases with Grade royal or aristocratic owners and provenances, along with O Cape Tinted Colour increases with Grade stories of derring-do, can be traced back to the seventeenth and eighteenth centuries. Three are now in museum collections: P Cape Tinted Colour increases with Grade the Hope in the Smithsonian Institute, to whom it was donated Q Cape Tinted Colour increases with Grade in 1958 by Harry Winston, the America diamond dealer and R Cape to Dark Cape Tinted Colour increases with Grade jeweller; La Grand Condé has pride of place in the Condé Museum, Château de Chantilly, Chantilly, France and the S-Z Dark Cape Tinted Deep Colour

ANTIQUES INFO - September/October 13 Diamonds

7 11 16 21 Quality certified platinum & diamond ring, brilliant cut 18ct gold solitaire diamond 1 18ct gold solitaire diamond Pair of coloured diamond central diamond 1.03cts, ring, emerald cut diamond colour i-j, clarity VS, 3 The most expensive diamonds twist ring, brilliant cut single-stone ear-studs, round claw set in white gold to the smaller diamonds each side in our archives. Two-stone diamond claw set in white old brilliant-cut stones each yellow gold hoop, Anchor of shoulder, ring size O 1/2, diamond pendant, 4.96 carats gold to the yellow gold hoop, approx 8.25mm dia, fancy Certificate stating diamond Anchor Cert certificate comm- and 4.11 carats, highest GIA certificate stating: weight yellow and brown in rex claw weight as ‘1.03’, colour ‘K’ issioned by Cuttlestones. colour scale grading. Halls 4.3ct, clarity ‘I1’ and colour settings, certificate from Gem and clarity ‘VVS 2’, weight Cuttlestones, Penkridge. Mar Fine Art, Shrewsbury. Oct 10. ‘K’, weight approx 5gms. Testing Laboratory of Great approx 3gms. Halls, 13. HP: £2,100. ABP: £2,478. HP £180,000. ABP: £212,400. Halls, Shrewsbury. Oct 12. Britain stating yellow diamond Shrewsbury. Oct 12. HP: HP: £10,500. ABP: £12,390. weighs 2.37cts, is ‘fancy £1,350. ABP: £1,593. 1 yellow’ and ‘natural colour’. Bearne’s, Exeter. June 05. HP 2 8 £6,800. ABP: £8,104. 22 Stamped 18ct white gold 3 Rare diamond three stone Lady’s/gent’s diamond set stone diamond ring, 3 old cut ring, 3.6 cts, internally 12 ring, 6 channel set rows of Good quality old European diamonds approx 0.97ct, flawless, colour grade D. baguette cut stones on heavy cushion cut diamond solitaire Diamond solitaire ring, 0.65ct, 0.55ct, claw set to Dreweatt Neate, Donnington. tapering white gold shank, ring set in 18ct white gold brilliant cut stone 1.09cts, knife edge shoulders, recent July 06. HP £56,000. 154 stones, total approx 6.93 mount, 4 double claw collet, claw set to 2 shoulders each valuation for insurance cts, colour assessed as G-H, knife edge shoulder shank, pave set 3 small diamonds, assessing diamonds as I-J clarity assessed VS-SI, white weight 2.93ct, size 9.76 x unmarked plain white metal colour, I1 clarity. Frank gold, cast setting with very 8.89 x 4.73 mm, clarity SI2, shank, size L 1/2, with BGI Marshall, Knutsford. Mar 13. minor gaps at ends where colour N/O, total weight 5.1 certificate stating diamond is HP: £1,100. ABP: £1,298. 3 stones meet metal, tested 18ct, grams, ring size O, hallmark colour grade E, clarity A6. size T or 9.1/2 US (20.7g) 18ct white gold Birmingham (SI1) Hartleys, Ilkley. Jun 12. 23 Impressive 18ct white gold boxed, valuation of £6,500 by TT. Willingham Auctions, HP: £4,700. ABP: £5,546. set solitaire diamond of dated 2003. A F Brock & Co Willingham. Feb 13. HP: 4.05cts with AnchorCert Ltd, Stockport. May 13. HP: £9,000. ABP: £10,620. 13 certificate stating stone to be £1,750. ABP: £2,065. old English brilliant cut, clarity VVS2, colour H, size The prices quoted are actual Hammer Prices (HP) 18 G. Gorringes, Lewes. Dec 11. Lady’s diamond cluster ring, followed by the Approximate HP: £37,000. ABP: £43,660. width at front 16mm, centre Buyer’s Price (ABP) which cluster of 7 brilliant cut includes an average buyer’s Solitaire diamond ring, brilliant cut stone, approx stones, 12 princess cut stones 4 premium of 15% + VAT. 2.5cts, claw set within bag- Platinum solitaire ring, set set in double row to either uette shoulders, platinum with a pear shaped brilliant side in channel setting, row shank, size H 1/2, colour J, of 13 baguette cut diamonds Platinum set solitaire cut diamond (approx 0.77ct, clarity P-1. Hartleys, Ilkley. to top & bottom, total dia- diamond ring, approx 3.84cts colour approx E/F). Richard Mar 13. HP: £4,600. mond weight 2.25cts, clarity with Precious Stone Labor- Winterton, Lichfield. Feb 13. 9 ABP: £5,428. HP: £1,500. ABP: £1,770. given as SI to SI2, colour atory diamond report stating given as H & I, all in 14ct Solitaire diamond ring, the stone as 3.84cts, colour F 19 yellow gold, size N or 6.1/2 cushion shape old brilliant 14 / rare white +, SI1, size M. US (12.3g) boxed. A F Brock cut stone of 9.5 x 8.5 x 5.8mm Gorringes, Lewes. Dec 12. & Co Ltd, Stockport. Feb 13. estimated mounted weight HP: £25,000. ABP: £29,500. HP: £1,000. ABP: £1,180. 3.65ct colour assessed as L- Tiffany & Co platinum set M (drawing some yellow) seven stone half eternity ring, clarity assessed as VSI to Victorian solitaire diamond channel set 7 round brilliant 5 white precious metal mount ring, diamond shoulders and cut diamonds, total diamond yellow gold shank, size N, and shank makers mark M.B approx 0.91cts, with original 24 18ct white gold set single but no other marks. Golding main stone wt. 2.20ct, colour box & retail replacement stone princess cut diamond Young & Thos. Mawer, I, clarity VS2. Hartleys, valuation from Tiffany & Co, Solitaire diamond ring, ring. with HRD certificate Lincoln. Aug 11. HP: £8,200. Ilkley. Mar 13. HP: £3,900. New York, stating diamonds emerald cut stone, baguette stating weight at 3.57cts ABP: £9,676. ABP: £4,602. to be of G colour, VS clarity, shoulders, plain platinum clarity VVSI, colour grade replacement value of $5000 shank, size M 1/2, total rare white (G), size M. (dated 2004). Frank diamond wt. 0.83ct, colour Gorringes, Lewes. Jun 11. Marshall, Knutsford. Mar 13. D, clarity V V 1/ 2. Hartleys, HP: £21,000. ABP: £24,780. Ilkley. Mar 13. HP: £980. 10 HP: £1,400. ABP: £1,652. 15 ABP: £1,156. 6 20 Edwardian 18ct gold mounted Art Deco single stone 25 all diamond set dress ring, diamond ring, old European central old cut yellow cut diamond, est.weight diamond approx 1ct, approx 1.50ct, claw set to sea contained within a border of Fine cushion shaped, old scroll collet, diamond set Solitaire diamond ring, 12 small old cut brilliant mine cut diamond solitaire shoulders, marked platinum. brilliant cut stone of 0.72cts, diamonds each approx .05ct Brilliant cut diamond, 1.02 ring, platinum mount, approx Finger size N¾. Diamond claw set to a plain white (gross weight 3.1 grammes - carats, VS2 colour G, still in 4.3 ct, est. colour G/H/I, est. est. approx colour H/I, metal shank, size M, colour ring size Q. Canterbury original packet. A F Brock & clarity approx VS1/2. Arnolds clarity SI1-SI2. Sworders, G, clarity V V S2. Hartleys, Auction Galleries, Kent. June Co Ltd, Stockport. Aug 11. Keys , Aylsham. Nov 12. HP: Stansted Mountfitchet. Feb 11. Ilkley. Mar 13. HP: £1,400. 13. HP £7,000. ABP: £8,400. HP: £920. ABP: £1,085. £19,500. ABP: £23,010. HP: £2,800. ABP: £3,304. ABP: £1,652. ANTIQUES INFO - September/October 13