{"product_id":"gia-certified-0-61-carat-marquise-alexandrite-diamond-platinum-drop-necklace","title":"GIA Certified 0.61 Carat Marquise Alexandrite Diamond Platinum Drop Necklace","description":"\u003cdiv\u003eGIA-certified 0.61 carat marquise cut natural untreated Brazilian alexandrite and 1.10 carat total weight round brilliant diamond halo drop pendant necklace in 18K white gold and platinum, featuring a transparent color-change alexandrite graded bluish green to purple by GIA in a diamond halo pendant suspended from a graduating diamond station connector on a polished white gold bar link chain.\u003c\/div\u003e\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\u003cdiv\u003ePendant measures 13.5 x 9.6mm; necklace adjusts from 16 to 18 inches via extender chain; GIA Report No. 1549806847; 11.1 grams total.\u003c\/div\u003e\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\u003cdiv\u003e\u003cstrong\u003eProduct Specifications:\u003c\/strong\u003e\u003c\/div\u003e\u003cul\u003e\n\u003cli\u003eItem Type: GIA Certified Diamond Halo Drop Pendant Necklace\u003c\/li\u003e\n\u003cli\u003eMetal: 18K White Gold and Platinum\u003c\/li\u003e\n\u003cli\u003eChain Length: 16 to 18 inches (extender chain for multiple placement)\u003c\/li\u003e\n\u003cli\u003eChain Style: Polished white gold flat bar link with graduating diamond stations\u003c\/li\u003e\n\u003cli\u003ePendant Size: 13.5 x 9.6mm\u003c\/li\u003e\n\u003cli\u003eTotal Weight: 11.1 grams\u003c\/li\u003e\n\u003cli\u003eCertification: GIA Alexandrite Origin Report No. 1549806847\u003c\/li\u003e\n\u003c\/ul\u003e\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\u003cdiv\u003e\u003cstrong\u003eCenter Stone Details:\u003c\/strong\u003e\u003c\/div\u003e\u003cul\u003e\n\u003cli\u003eSpecies: Natural Chrysoberyl\u003c\/li\u003e\n\u003cli\u003eVariety: Natural Alexandrite\u003c\/li\u003e\n\u003cli\u003eGIA Report No.: 1549806847\u003c\/li\u003e\n\u003cli\u003eReport Date: March 31, 2026\u003c\/li\u003e\n\u003cli\u003eCarat: 0.61 carats\u003c\/li\u003e\n\u003cli\u003eShape: Marquise\u003c\/li\u003e\n\u003cli\u003eMeasurements: 9.66 x 4.66 x 1.95mm\u003c\/li\u003e\n\u003cli\u003eColor: Bluish Green changing to Purple\u003c\/li\u003e\n\u003cli\u003eTransparency: Transparent\u003c\/li\u003e\n\u003cli\u003eCutting Style Crown: Brilliant Cut\u003c\/li\u003e\n\u003cli\u003eCutting Style Pavilion: Step Cut\u003c\/li\u003e\n\u003cli\u003eGeographic Origin: Brazil (GIA expert opinion)\u003c\/li\u003e\n\u003cli\u003eTreatment: Untreated (natural, no heat)\u003c\/li\u003e\n\u003cli\u003eMohs Hardness: 8.5\u003c\/li\u003e\n\u003cli\u003eBirthstone: June\u003c\/li\u003e\n\u003c\/ul\u003e\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\u003cdiv\u003e\u003cstrong\u003eDiamond Details:\u003c\/strong\u003e\u003c\/div\u003e\u003cul\u003e\n\u003cli\u003eType: Natural Diamond\u003c\/li\u003e\n\u003cli\u003eTotal Carat Weight: 1.10 carats\u003c\/li\u003e\n\u003cli\u003eCut: Round Brilliant\u003c\/li\u003e\n\u003cli\u003eSetting: Prong-set halo surrounding alexandrite and graduating diamond station connector above\u003c\/li\u003e\n\u003c\/ul\u003e\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\u003cdiv\u003e\u003cstrong\u003eAbout the Setting:\u003c\/strong\u003e\u003c\/div\u003e\u003cdiv\u003eThe pendant is constructed with a marquise alexandrite in a prong setting completely encircled by a continuous round brilliant diamond halo that follows the elongated marquise outline of the stone, suspended via a single round brilliant connector from a graduating diamond station link that bridges the pendant to the polished flat bar link chain above. The flat bar link chain alternates polished white gold rectangular bars with small articulated connectors transitioning into graduating diamond stations as the chain approaches the pendant — a design detail that creates a natural visual progression from the geometric chain to the diamond-encircled alexandrite below. The extender chain provides 16 and 18 inch wearing options to accommodate different necklines and styling preferences.\u003c\/div\u003e\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\u003cdiv\u003e\u003cstrong\u003eAbout the Stone:\u003c\/strong\u003e\u003c\/div\u003e\u003cdiv\u003eThis GIA-certified 0.61 carat marquise alexandrite — GIA Report No. 1549806847 dated March 31, 2026 — is graded bluish green changing to purple with transparent clarity, a brilliant crown over step-cut pavilion, and confirmed Brazilian geographic origin. The marquise shape at 9.66 x 4.66mm provides an elongated, pointed silhouette that accentuates the color-change phenomenon across the stone's longest dimension, allowing both the bluish green daylight color and the purple incandescent color to display across the full face of the gem with maximum visual impact. Untreated Brazilian alexandrite with a GIA origin report and strong bluish green to purple color change is among the most sought-after colored gemstone categories globally — the combination of documented natural treatment status, confirmed Brazilian origin, independent GIA certification, and the alexandrite color-change phenomenon in a marquise cut is genuinely rare in the current fine jewelry market at any price point.\u003c\/div\u003e","brand":"ASSAY","offers":[{"title":"Default Title","offer_id":47712126795966,"sku":"POTC2646N","price":4311100.0,"currency_code":"JPY","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0508\/5724\/6910\/files\/GIA-Certified-0_61-Carat-Marquise-Alexandrite-Diamond-Platinum-Drop-Necklace-Necklace.jpg?v=1782338302","url":"https:\/\/jp.assayjewelers.com\/ja\/products\/gia-certified-0-61-carat-marquise-alexandrite-diamond-platinum-drop-necklace","provider":"ASSAY","version":"1.0","type":"link"}