Posts by rashid

    Two Kashmir sapphire lots, Lot 1752 and Lot 1938, that appeared at Sotheby's Hong Kong Magnificent Jewels & Jadeite Sale on October 7, 2014 appears to have broken the price-per-carat world record for a Kashmir sapphire set by the 28.18-carat, square emerald-cut Kashmir sapphire, at the Sotheby's New York, April 29, 2014 Magnificent Jewels Sale.


    Lot 1752 - Fine Sapphire, Emerald and Diamond Ring by Cartier - with a pre-sale estimate of HKD6,000,000 — 7,500,000 (USD773,640 - 967,050) sold for a much enhanced price of HKD18,040,000 (USD2,326,078). The centerpiece of this ring is a 12.00-carat, step-cut Kashmir blue sapphire, flanked by calibré-cut emeralds on the shoulders and hoop of the ring, together weighing 1.60 carats, decorated by circular-cut diamonds and mounted in platinum. A lab report by AGL certified that the 12.00-carat sapphire is natural, and of Kashmir origin, with no gemological evidence of heat treatment, and posseses the velvety-blue color characteristic of Kashmir blue sapphires. The price-per-carat of this blue sapphire works out to USD193,839 which is above the ppc-value of the 28.18-carat, square emerald-cut Kashmir sapphire of USD180,731. Hence, the 12.00-carat step-cut Kashmir blue sapphire sets a new world record for ppc-value of USD193,839.


    The other Kashmir sapphire lot, 1938 was an "Exceptional and Very Rare Sapphire and Diamond Ring" centering on a step-cut sapphire weighing 17.16 carats, known as "The Imperial Kashmir" surrounded by circular-cut and brilliant-cut diamonds together weighing 6.00 carats and mounted in platinum. Three lab reports by AGL, GGL and SSEF certify the 17.16-carat sapphire as natural and of Kashmir origin, with no no indications of heating. A supplemental letter issued by AGL, further states, that the sapphire displays a soft velvety "cornflower blue" colour that is commonly seen in sapphires of Kashmir origin...Large emerald cut Kashmir sapphires are rarely encountered in today's market. The provenance, size and intrinsic quality of the present 17.16 ct gem only adds to its rarity and desirability...In consideration of the special provenance, size and quality attributes of this exceptional gem, it has been named: "The Imperial Kashmir." A pre-sale estimate of HKD22,000,000 — 28,000,000 (USD2,836,680 - 3,610,320) was placed on this Kashmir Sapphire Lot, which sold for HKD 31,480,000 (USD4,059,031). This works out to a price-per-carat value of USD236,540 a new world record for price-per-carat for a Kashmir sapphire.

    At least four Animal and Plant Motif Jewelry Lots appeared at Christie's London, South Kensington, Jewels At South Kensington Sale, held on April 7, 2009. These lots are Lot 3, Lot 136, Lot 138 and Lot 140. These lots except for Lot 136 were designed by unknown designers and did not make much of an impression at the auctions. Yet these lots are worth considering in detail due to the artistic excellence of these pieces.


    Lot 3 - Pre-sale estimate - US$1,492 - $2,238 Price realized - US$3,680
    Lot 136 - Pre-sale estimate - US$2,984 - $4,476 Price realized - US$4,048
    Lot 138 - Pre-sale estimate - US$2,984 - $3,730 Price realized - US$4,048
    Lot 140 - Pre-sale estimate - US$1,790 - $2,238 Price realized - US$2,208


    Lot 3 - is an antique "Victorian Diamond Bird Brooch" designed in the Late Victorian Period around 1890. The brooch is designed as a pavé-set diamond swallow with cabochon-ruby-set eyes, mounted on a pavé-set diamond crescent moon.


    Lot 136 - is a "Diamond, Coral and Emerald Owl Brooch - by Gübelin," signed with the maker's mark for Gübelin. The brooch is designed as a stylized wirework owl perched on a branch of a tree made of yellow-gold. The body of the bird and head is covered with navette-shaped coral feathers, so are two leaves of the branch. Each of the eyes are set with pave-set diamonds and a single cabochon-cut emerald.


    Lot 138 - is a "Set of Three Diamond and Gem Bee Brooches" - Each of the bees is set with calibre-cut blue sapphires, rubies or emeralds in addition to diamonds.The abdomen of the bee is set with calibre-cut colored gemstone and diamond. The thorax is set as a cluster of colored gemstone center and diamond surround. The eyes are set with cabochon-cut rubies. The wings are set with diamonds and the legs of yellow-gold wire.


    Lot 140 - is a "Colored Diamond and Sapphire Butterfly Brooch" - The thorax and abdomen of the butterfly is pavé-set with brown diamonds. The eyes are set with blue sapphires. The antenna made of yellow-gold is set with a brown diamond at its distal end. The wings are pavé-set with blue sapphires, and the borders and veins in the wing pavé-set with brilliant-cut brown diamonds. The rear wing terminals are pavé-set as clusters of brown diamonds.

    Two Burmese Blue Sapphire lots appeared at Christie's Jewels : The Hong Kong Sale held on May 26, 2009. These lots are Lot 1653 and Lot 1703.


    Lot 1653 that sold for an impressive US$484,764 was an 18k white gold ring set with a 16.38-carat, cushion-cut, Burma sapphire, flanked by two triangular-shaped diamonds, appropriately titled - An Impressive Sapphire And Diamond Ring. Gubelin Gem Lab certified the Burma origin of the stone without any heat enhancement. The price-per-carat of this blue sapphire works out to US$29,595.


    Lot 1703 was a Pair of Sapphire, Pearl and Diamond Ear-Pendants. Each of the ear-pendants suspends an oval cabochon-cut Burma blue sapphire, weighing 9.06 carats and 8.42 carats, joined to two circular rose-cut diamonds separated by a shperical pearl spacer ending in diamond hooks. GRSL certified the Burma origin of the two sapphires with no indications of thermal enhancement. The lot sold for US$56,707 above the estimated range of US$27,219 - $38,884. The ppc of the blue sapphires works out to US$3,244

    The images of 49.47-carat, cut-cornered rectangular step-cut Ceylon blue sapphire and the 9.18-carat modified pear-shaped Ceylon blue sapphire uploaded by Peter, appear to show the characteristic hue, tone and saturation of Ceylon blue sapphires, which are generally lighter and brighter than Kashmir and Burma sapphires, and possess a saturated, evenly distributed, medium blue color, with good transparency and clarity. The clarity of the 9.18-carat Ceylon blue sapphire is excellent, but the 49.47-carat, rectangular step-cut Ceylon blue sapphire appears to be slightly included.


    However, what puzzles me most are the weights of the modified pear-shaped Ceylon blue sapphire and almost similar shaped, slightly smaller diamond in the "Toi et Moi" ring. While the Ceylon blue sapphire weighs 9.18 carats, the almost similar shaped but slightly smaller, colorless diamond weighs only 4.93 carats. In otherwords, if we take a blue sapphire and a diamond of similar shape and size, the blue sapphire has a weight greater than the diamond. What is the possible explanation for this ?

    Thanks Lareef for your detailed and in-depth analysis of whole stone prices and price-per-carat values of Kashmir sapphires that appeared at various public auctions from 2007 to 2014. It appears that you have divided the 26 Kashmir blue sapphires considered into three broad categories.

    1st-category - Sapphires falling above the range of US$100,000 per carat - Sapphire Nos. 1 to 11
    2nd-category - Sapphires falling within the range of US$50,000 to US$100,000 per carat - Sapphire Nos 12 to 21.
    3rd-category - Sapphires falling below the range of US$50,000 per carat. - Sapphire Nos. 22 to 26.


    I don't know whether it would be appropriate to name the three categories as High Grade, Medium Grade and Low Grade Kashmir sapphires.


    High Grade - above US$100,000 per carat - Sapphires 1 to 11.
    Medium Grade - between US$50,000 to 100,000 per carat - Sapphires 12 to 21.
    Low Grade - below US$50,000 per carat - Sapphires 22 to 26.

    Thanks Mike for your update. Image of Lot 1560 was of special interest. This is the first time I am seeing an image of a heat treated blue sapphire. The treatment seems to have done justification to the hue and tone of the blue color of the sapphire, but on the contrary has had a devastating effect of the ppc-value of the stone, which has plunged to absurdly low levels after the detection of the treatment !!!

    Three other Kashmir sapphire lots - Lot 81, Lot 250 and Lot 332 - appeared at Sotheby's Geneva Magnificent Jewels Sale held on November 13, 2013.

    Lot 81 was a Sapphire and Diamond Ring set with a 5.48-carat, cut-cornered step-cut Kashmir Sapphire, between tapered baguette diamond shoulders. Two reports by SSEF and Gubelin certified the Kashmir origin of the stone without any heat enhancement. The lot sold for USD 273,567 between the pre-sale estimate of USD 201,633 - 299,725. This works out to a price-per-carat value of USD 49,920.


    Lot 250 was a Sapphire and Diamond Ring designed by Ronald Abram, set with a 4.52-carat, cushion-shaped sapphire between heart-shaped diamond shoulders. Two lab reports by SSEF and GGL certified the Kashmir origin of the stone with no indications of heat enhancement. The lot was sold for USD 358,580 which was 2.3 times the lower estimate of USD 152,587 and 1.8 times the upper estimate of USD 201,633. The ppc-value of this Kashmir sapphire works out to USD 79,332.


    Lot 332 - the 21.42-carat, cushion-cut Kashmir sapphire has already been highlighted by Maryjewel on January 30, 2014




    The 15.35-carat, cushion modified brilliant-cut alexandrite, that appeared at the Government Auction Assets sale held online on April 29, 2012 and highlighted by Yousuf, was certified by GIA as an alexandrite. The GIA certificate described its color change as Brownish Green-Yellow to Brown-Yellow. This means that apart from green to bluish-green in daylight and red to purplish-red in incandescent light, shown by fine alexandrites other color changes are also possible in lesser quality alexandrites. What is the chemistry behind these dramatic color changes and what are the ranges in color changes possible in alexandrites ?



    Even though the image uploaded by Mikegem is described as a pink star sapphire, the image appears to have a violet or purple hue, which are also secondary hues of rubies. This may be a visual distortion, but the intensity of the color is strong enough to define clearly the six rays of the star. In this context, one is not certain whether identifying this stone as a pink star sapphire is justified, even though the origin of the stone is Sri Lanka.

    The pink sapphires/pink rubies incorporated in the Cartier Jewel uploaded by shah, are indeed the rare and beautiful stones, prized equally with the ruby, possessing a light ruby color, with a strong dash of pink in it, as described by J.F.Stewart in 1855, which he referred to as "Pink Rubies."
    "Ceylon" ruby was once a common term for light red to pinkish ruby that in most cases is now referred to as pink sapphire.
    Given the fact that light-red to pinkish color of rubies is associated with the name "Ceylon" is it not possible that gem-testing laboratories may be tended to name any light-red to dark-pink ruby/sapphire as "Pink Sapphire" once they establish the origin of the stone as Ceylon/Sri Lanka, especially in the context that no sharp distinction exists between rubies and pink sapphires ?

    A casual examination of the PPC values given by Yousuf indicates that the size of the blue sapphires might be related to the large disparity in ppc values. I may be subject to correction, but sapphire No.1 with an enormous weight of 102.61 carats selling for a staggering USD 4,203,118 is the cause of the disparity. In comparison, sapphires 2 to 6 with lesser weights sold for only around USD 100,000 or less.

    Another Kashmir blue sapphire, not so significant in terms of its size but with all the exceptional qualities of Kashmir sapphires such as its lovely saturated velvety-blue color, mounted on a platinum ring by Tiffany & Co. with diamond shoulders, appears to have set a record-breaking price-per-carat value at Christie's New York in December 2012. The cushion-cut velvety-blue sapphire weighing 8.91 carats sold for a stunning US$ 1.37 million, which was 5.5 times the lower estimate of of US$ 250,000 and almost 4 times the upper estimate of US$ 350,000. The price-per-carat achieved by this sapphire was US$ 153,759,considered by Christie's as a new world record for price-per-carat for a Kashmir sapphire. I do not know where in the list given above would this Kashmir sapphire fit in ?

    Thanks for taking all the trouble in giving us an almost total and exhaustive reply on white/colorless diamonds of Golconda origin. The images you posted were of excellent quality, and helped to drive home the point you were trying to make, on the superior qualities of these historic diamonds. I can now appreciate the fact that India was indeed a treasure-trove of these priceless diamonds for over two millennia, catering to the ancient kingdoms and monarchies spread across the world.

    If as you said the Nautilus shell wall is made up of two layers, an outer matte, white layer and an inner blue-gray shiny nacreous layer, made of conchiolin and aragonite, why are Nautilus pearls non-nacreous and porcellaneous, with a matte-like appearance lacking the iridescence of nacreous pearls?