{"product_id":"ceylon-blue-sapphire-4-15ct-cushion","title":"4.15ct Ceylon Blue Sapphire - Cushion Cut","description":"\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eGem Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eNatural Sapphire\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCarat Weight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e4.15 ct\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDimensions\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e10.51 x 7.51 x 5.16 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eShape\/Cut\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eRectangular Cushion Faceted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eColour\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eRoyal Blue\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTreatment\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eTraditional Heat Treatment\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOrigin\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eCeylon (Sri Lanka)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCertification\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eCeylon Gem Lab (CGL)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003cp\u003eThis 4.15ct Ceylon blue sapphire is an extraordinary stone, a museum-quality royal blue gem of a size and intensity that places it among the finest sapphires available in the Australian market. The deep, saturated royal blue radiates from every angle of the rectangular cushion cut, which has been expertly faceted to balance maximum brilliance with the rich colour depth that defines world-class blue sapphires.\u003c\/p\u003e\n\n\u003cp\u003eAt 10.51 x 7.51 mm, this stone has commanding proportions. It is the kind of sapphire that anchors a significant piece of jewellery, a cocktail ring that draws every eye in the room, a pendant of undeniable presence, or a centrepiece in a high-value gemstone collection.\u003c\/p\u003e\n\n\u003ch2\u003eOrigin \u0026amp; Certification\u003c\/h2\u003e\n\n\u003cp\u003eThis sapphire originates from Ceylon (Sri Lanka), the island that has produced some of the most famous sapphires in history, including the 423-carat Logan Sapphire and the sapphire in Princess Diana's engagement ring. Ceylon's geological conditions create blue sapphires with a distinctive velvety quality and balanced saturation that no other origin consistently replicates.\u003c\/p\u003e\n\n\u003cp\u003eThis stone has been enhanced through traditional heat treatment, a standard practice that improves colour saturation and clarity. The Ceylon Gem Lab (CGL) has examined this sapphire and certified its natural origin, 4.15ct weight, royal blue colour grade, and treatment status. CGL is one of Sri Lanka's most respected gemological laboratories, and their certification carries significant weight in the international gem trade.\u003c\/p\u003e\n\n\u003ch2\u003eInvestment-Grade Rarity\u003c\/h2\u003e\n\n\u003cp\u003eFine blue sapphires over 4 carats with strong royal blue colour are genuinely rare in the global market. At this size and quality level, sapphires transition from jewellery stones to investment-grade assets with tangible collector value:\u003c\/p\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize rarity:\u003c\/strong\u003e Fewer than 1% of gem-quality blue sapphires mined exceed 3 carats. At 4.15 carats, this stone sits in an elite weight category where each additional carat carries exponential price premium.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColour grade:\u003c\/strong\u003e Royal blue is the most sought-after colour in the sapphire market. The combination of this colour with 4ct+ size creates a specimen that auction houses and serious collectors actively seek.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProvenance:\u003c\/strong\u003e Ceylon origin with CGL certification provides the documentation trail that underpins long-term value retention. Provenance-verified sapphires consistently outperform undocumented stones at resale.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMarket trend:\u003c\/strong\u003e Prices for large, certified Ceylon blue sapphires have appreciated steadily over the past decade, driven by shrinking supply from Sri Lanka's alluvial deposits and growing demand from Asian and Australian collectors.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhy This Sapphire\u003c\/h2\u003e\n\n\u003cp\u003eAt $18,000 AUD, this 4.15ct Ceylon blue sapphire represents a significant acquisition. And one justified by its exceptional combination of size, colour, origin, and certification. This is a stone for the buyer who understands that world-class gemstones are finite, and that quality at this level holds its value across generations.\u003c\/p\u003e\n\n\u003cp\u003eThe rectangular cushion cut is the preferred shape for large sapphires because it retains colour intensity across the stone's full face-up area while delivering the brilliance that makes sapphires so captivating in jewellery. The 10.51 x 7.51 mm dimensions suit bold ring designs, statement pendants, and collector display settings.\u003c\/p\u003e\n\n\u003cp\u003eWhether you are adding a cornerstone piece to a private gemstone collection, commissioning a bespoke heirloom ring, or acquiring a tangible asset with documented provenance, this sapphire stands in a category that few stones can match.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eRelated:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/collections\/blue-sapphire\"\u003eBrowse our full Ceylon Blue Sapphire collection\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/ceylon-blue-sapphire-3-06ct-cushion\"\u003eCompare: 3.06ct Ceylon Blue Sapphire Cushion\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdetails\u003e\n\u003csummary\u003eIs this sapphire heated?\u003c\/summary\u003e\n\u003cp\u003eYes. This sapphire has undergone traditional heat treatment, a standard practice in the gemstone industry. Heat treatment enhances colour and clarity and is universally accepted by gemological laboratories and auction houses. The CGL certificate discloses the treatment status.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003cdetails\u003e\n\u003csummary\u003eIs a 4-carat blue sapphire a good investment?\u003c\/summary\u003e\n\u003cp\u003eBlue sapphires over 4 carats with strong colour and certified Ceylon origin are genuinely rare and have shown consistent price appreciation over the past decade. The combination of CGL certification, royal blue colour grade, and 4.15ct weight positions this stone in the investment-grade category. As with any gemstone acquisition, independent certification and documented provenance are essential for long-term value.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003cdetails\u003e\n\u003csummary\u003eHow does this sapphire compare to smaller Ceylon blue sapphires?\u003c\/summary\u003e\n\u003cp\u003eAt 4.15 carats, this stone is in an entirely different rarity class. While sub-carat and 1-2ct Ceylon blue sapphires are more readily available, stones above 4 carats with royal blue saturation are scarce enough to be actively sought by collectors and investors. The price per carat increases exponentially with size in high-quality sapphires.\u003c\/p\u003e\n\u003c\/details\u003e","brand":"My Precious Gems","offers":[{"title":"Default Title","offer_id":43776405012595,"sku":"MPG-BS-0415","price":18000.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0670\/6400\/4723\/files\/21.png?v=1768221975","url":"https:\/\/mypreciousgems.com.au\/products\/ceylon-blue-sapphire-4-15ct-cushion","provider":"My Precious Gems","version":"1.0","type":"link"}