{"product_id":"1-66-ct-radiant-cut-yellow-sapphire-unheated-loose-gemstone","title":"1.66 ct Natural Unheated Yellow Sapphire – Radiant Cut | AGCL Certified | Sri Lanka (Ceylon)","description":"\u003cp\u003eA natural 1.66 carat yellow sapphire in a radiant cut, completely unheated and documented on AGCL Report #M2513593. The radiant cut combines the rectangular outline of a step cut with brilliant faceting — producing more light return than an emerald cut while maintaining the modern, architectural silhouette. In an unheated yellow sapphire at 1.66 carats, this format delivers the golden color with maximum sparkle across the face, creating a vivid and lively presentation.\u003c\/p\u003e\n\n\u003cdiv style=\"border: 2px solid #5b2c6f; border-radius: 10px; padding: 20px 24px; margin: 28px 0; background-color: #f9f5fc;\"\u003e\n\u003ch2 style=\"margin-top: 0; margin-bottom: 12px; color: #4a235a;\"\u003eExpert Opinion\u003c\/h2\u003e\n\u003cp style=\"font-weight: 600; margin-bottom: 6px;\"\u003e\u003ca href=\"https:\/\/crescentgems.com\/pages\/ahmed-shareek-about-the-owner\" style=\"color: #4a235a; text-decoration: underline;\"\u003eAhmed Shareek\u003c\/a\u003e's Assessment\u003c\/p\u003e\n\u003cp style=\"font-style: italic; margin-bottom: 0;\"\u003e\"Unheated yellow sapphire with this much golden saturation is already uncommon. Cutting it as a radiant, rather than the standard emerald cut most rectangular sapphires receive, adds real sparkle — the brilliant faceting layered onto that step-cut outline returns far more light to the eye than a pure step cut can.\"\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003e\u003cspan role=\"text\"\u003e\u003cstrong\u003eRarity Analysis\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h2\u003e\n\n\u003cp\u003eUnheated yellow sapphire with vivid, loupe-clean color in this size range represents a narrow slice of what's actually offered on the market, and the radiant cut narrows the field further.\u003c\/p\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e This is a vivid, medium-light-toned yellow with genuine saturation — most unheated yellow sapphire on the market leans pale, since heat treatment is the standard route to reaching this level of golden color.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSize:\u003c\/strong\u003e At 1.66 carats, this stone sits above the sub-1-carat range where most affordable unheated yellow sapphire is concentrated.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTreatment:\u003c\/strong\u003e The majority of yellow sapphire sold commercially is heat-treated to intensify or clarify color; a stone with no thermal history is a genuine minority within the category.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCut:\u003c\/strong\u003e Radiant is a far less common cut choice for sapphire than oval, cushion, or round — most cutting decisions favor those shapes for yield and color retention, so a radiant-cut sapphire turns up less often in general inventory, and even less often in yellow.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocumentation:\u003c\/strong\u003e AGCL Report #M2513593 independently documents this stone's weight, dimensions, color, and lack of heating — a level of third-party verification that isn't attached to every stone on the market.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCombined effect:\u003c\/strong\u003e Vivid unheated color, above-average size, an uncommon cut choice, and independent lab documentation rarely line up on a single stone — together they place this sapphire in a smaller, harder-to-replace category than any one factor alone.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003e\u003cspan role=\"text\"\u003e\u003cstrong\u003eBuying Guidance\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h2\u003e\n\n\u003cp\u003eA few practical points to weigh before purchasing this specific stone:\u003c\/p\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eJudge the light performance in motion:\u003c\/strong\u003e A radiant cut layers brilliant crown faceting onto a step-cut pavilion, so its sparkle pattern reads differently from a pure step cut like an emerald cut — ask for video in a couple of lighting setups to see how it performs before you commit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfirm the setting protects the corners:\u003c\/strong\u003e The cut corners of this octagonal radiant reduce chipping risk compared to a sharp-cornered rectangle, but check that your chosen setting's prong placement still guards them, especially given the stone's 6.80 × 5.40 × 4.56 mm profile.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVerify the unheated claim independently:\u003c\/strong\u003e Ask to see AGCL Report #M2513593 directly rather than relying on the listing description alone — the report documents the treatment status in writing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeigh availability against the cut:\u003c\/strong\u003e Because radiant-cut sapphire is less common than oval or cushion material, expect fewer directly comparable stones to shop against if you wait — that scarcity is worth factoring into your timeline.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTry Before You Buy:\u003c\/strong\u003e Request additional photos or a live video call to see the stone's faceting and golden color in hand before finalizing your purchase.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003e\u003cspan role=\"text\"\u003e\u003cstrong\u003eLearn More About This Gemstone\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/crescentgems.com\/blogs\/information-pages-complete-guide\/what-is-an-unheated-sapphire\"\u003eUnheated Sapphire Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/crescentgems.com\/blogs\/information-pages-complete-guide\/natural-sapphires-online-premium-gemstones\"\u003eHow to Buy Natural Sapphires Online\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/crescentgems.com\/blogs\/information-pages-complete-guide\/how-to-commission-custom-sapphire-ring\"\u003eCustom Ring Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/crescentgems.com\/blogs\/information-pages-complete-guide\/sapphire-buying-guide\"\u003eSapphire Buying Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/crescentgems.com\/blogs\/information-pages-complete-guide\/yellow-sapphire-buyers-guide\"\u003eYellow Sapphire Buyer's Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/crescentgems.com\/blogs\/information-pages-complete-guide\/radiant-cut-yellow-sapphires-the-complete-guide-to-color-cut-quality-and-buying-right\"\u003eRadiant Cut Yellow Sapphires — The Complete Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/crescentgems.com\/blogs\/information-pages-complete-guide\/emerald-cut-sapphire-guide\"\u003eEmerald Cut Sapphire — The Complete Guide\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv style=\"border: 2px solid #5b2c6f; border-radius: 10px; padding: 20px 24px; margin: 28px 0; background-color: #f9f5fc;\"\u003e\n\u003ch2 style=\"margin-top: 0; margin-bottom: 14px; color: #4a235a;\"\u003eGemstone Data — At a Glance\u003c\/h2\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; font-size: 0.95em;\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600; width: 42%;\"\u003eItem #\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eCG8351\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eCarat Weight\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003e1.66 ct\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eSpecies\/Variety\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eNatural Yellow Sapphire (Corundum)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eShape\/Cut\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eRadiant Cut (Octagonal)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eDimensions\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003e6.80 × 5.40 × 4.56 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eColor\/Intensity\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eYellow\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003ePhenomenon\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eNone\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eTreatment\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eUnheated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eOrigin\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eSri Lanka (Ceylon) — store's own assessment; not addressed by the AGCL report\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eClarity\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eLoupe Clean\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eTransparency\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003eTransparent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee; font-weight: 600;\"\u003eHardness\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px; border-bottom: 1px solid #e5d9ee;\"\u003e9 (Mohs)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 6px 8px; font-weight: 600;\"\u003eCertification\u003c\/td\u003e\n\u003ctd style=\"padding: 6px 8px;\"\u003eAGCL Report #M2513593\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003e\u003cspan role=\"text\"\u003e\u003cstrong\u003eFeatures\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003eSKU: CG8351\u003c\/li\u003e\n\u003cli\u003eCarat Weight: 1.66 Carats\u003c\/li\u003e\n\u003cli\u003eVariety: Yellow Sapphire\u003c\/li\u003e\n\u003cli\u003eDimensions: 6.80 x 5.40 x 4.56 mm\u003c\/li\u003e\n\u003cli\u003eShape: Octagonal\u003c\/li\u003e\n\u003cli\u003eCut Style: Radiant Cut\u003c\/li\u003e\n\u003cli\u003eOrigin: Sri Lanka (Ceylon)\u003c\/li\u003e\n\u003cli\u003eTreatment: Unheated\u003c\/li\u003e\n\u003cli\u003eColor: Yellow\u003c\/li\u003e\n\u003cli\u003eClarity: Loupe Clean — eye-clean, no visible inclusions under normal viewing\u003c\/li\u003e\n\u003cli\u003eTransparency: Transparent\u003c\/li\u003e\n\u003cli\u003eHardness: 9 on the Mohs scale\u003c\/li\u003e\n\u003cli\u003eCertification: AGCL Report #M2513593\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003e\u003cspan role=\"text\"\u003e\u003cstrong\u003eOne of a Kind\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h2\u003e\n\n\u003cp\u003eThis is a single natural gemstone, not a lab-created or manufactured stone — no two are exactly alike. Once sold, this particular 1.66 ct yellow sapphire will not be available again.\u003c\/p\u003e\n\n\u003ch2\u003e\u003cspan role=\"text\"\u003e\u003cstrong\u003eCare\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h2\u003e\n\n\u003cp\u003eClean with warm soapy water and a soft brush. Avoid ultrasonic cleaners and harsh chemicals, and store separately from harder or abrasive materials to prevent scratching.\u003c\/p\u003e\n\n\u003cp\u003eThis 1.66 ct unheated radiant yellow sapphire has been hand-selected for the brightness of its yellow and the quality of its radiant faceting — the combination that makes this an unusual and compelling yellow sapphire. Documented on AGCL Report #M2513593, it carries no thermal history — the golden color is entirely natural, exactly as formed.\u003c\/p\u003e\n\n\u003ch2\u003e\u003cspan role=\"text\"\u003e\u003cstrong\u003ePerfect Uses\u003c\/strong\u003e\u003c\/span\u003e\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003eEngagement ring center stone in yellow gold\u003c\/li\u003e\n\u003cli\u003eJyotish \/ Vedic astrological use (natural Pukhraj)\u003c\/li\u003e\n\u003cli\u003eCustom pendant or cocktail ring\u003c\/li\u003e\n\u003cli\u003eCollectors of unheated yellow sapphires in unusual cuts\u003c\/li\u003e\n\u003cli\u003eAnniversary gift\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Crescent Gems","offers":[{"title":"Default Title","offer_id":42773319188547,"sku":"CG8351","price":1870.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0658\/8982\/8931\/files\/1112023001_d31be951-a0b7-406f-bd81-ed785149a21c.jpg?v=1778348787","url":"https:\/\/crescentgems.com\/en-ca\/products\/1-66-ct-radiant-cut-yellow-sapphire-unheated-loose-gemstone","provider":"Crescent Gems","version":"1.0","type":"link"}