Fischer XRF Au750 (75.0%) & Mettler-Toledo Gravimetric Verification
The Rolex GMT-Master II Guinness / Zombie Grey & Black Cerachrom Reference 126713GRNR is a direct Swiss foundry specimen engineered in 18K Gold & 904L Oystersteel Rolesor (40.0 mm x 11.9 mm) with a certified Mettler-Toledo mass of 172.1g, Fischer XRF Au750 metallurgical verification, and Rolex Manufacture Cal. 3285 - 70h Power Reserve running at 28,800 vph (+0.8 s/d, 300 deg) with a 72-hour power reserve and 100m / 330 ft - Triplock Screw-Down rating.
Catalogued in our direct Swiss foundry Rolex assay archive under Specimen Code LAB-CNC-126713GRNR-W139, this Rolex GMT-Master II Guinness / Zombie Grey & Black Cerachrom Reference 126713GRNR is smelted and CNC-machined in 18K Gold & 904L Oystersteel Rolesor (40.0 mm x 11.9 mm). Prior to archival release, the completed assembly is weighed on a calibrated Mettler-Toledo balance at 172.1g and scanned via non-destructive Fischer XRF spectroscopy.
What Are the Horological & Metallurgical Benchmarks of Rolex GMT-Master II Ref. 126713GRNR?
The Rolex GMT-Master II Reference 126713GRNR is a precision-engineered luxury timepiece crafted in 18K Gold & 904L Oystersteel Rolesor (40.0 mm x 11.9 mm) with Hand-Finished Sunray Collector Dial with Hand-Finished Luminous Appliques & Hands, Precision Brushed & Polished 18K Rolesor Bezel with Anti-Reflective Scratch-Resistant Sapphire Crystal, and a verified Mettler-Toledo mass of 172.1g, because its Rolex Manufacture Cal. 3285 - 70h Power Reserve movement is regulated across six positions to chronometric tolerances with a 72-hour power reserve.
5 Core Foundry & Laboratory Assay Specifications:
- Foundry Specimen Entity: Rolex GMT-Master II Guinness / Zombie Grey & Black Cerachrom — Official Ref. 126713GRNR (Specimen LAB-CNC-126713GRNR-W139).
- XRF Metallurgical Assay: 18K Gold & 904L Oystersteel Rolesor certified for elemental composition and hallmark integrity.
- Mettler-Toledo Mass: 172.1g verified gravimetric parity matching the authentic manufacture reference.
- Chronometric Calibre: Rolex Manufacture Cal. 3285 - 70h Power Reserve beating at 28,800 vph (4 Hz) with 72-hour reserve and +0.8 s/d, 300 deg Witschi trace.
- Optical & Pressure Testing: Double anti-reflective sapphire crystal, Hand-Finished Sunray Collector Dial with Hand-Finished Luminous Appliques & Hands, and 100m / 330 ft - Triplock Screw-Down barometric sealing.
Within the Rolex GMT-Master II horological sub-silo, collectors also compare the Rolex GMT-Master Vintage Geneva Atelier Spec Ref. 6542 (114.4g) and the Rolex GMT-Master II Pepsi Red & Blue Cerachrom Geneva Atelier Spec Ref. 126710BLRO (143.8g).
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- Technical Research Monograph: Fischer XRF Au750 Spectrometry Watch Authentication SOP-750 (All 5 Journal Monographs)
- Homepage Master Register: Return to 18K FACTORY Homepage (Complete 774-Watch Solid 18K Gold & Pt950 Register)
- All-Brands Catalogue: Explore Complete 12-Maison Horological Catalogue (/shop/)
- Metallurgical & Escrow Verification: Fischer XRF Au750 Protocol • 3-Year Mechanical Warranty • Insured Armored Delivery
What laboratory instruments certify Reference 126713GRNR (Rolex)?
Every 18K Factory specimen is verified on three calibrated instruments on 4K video: a Mettler-Toledo analytical balance (172.1g), a Fischer XRF spectrometer (18K Gold & 904L Oystersteel Rolesor), and a Witschi Chronoscope (+0.8 s/d, 300 deg).
Does the 172.1g reading match the authentic original Rolex 126713GRNR weight?
Yes. Our CNC foundry machines the 18K Gold Rolesor case and bracelet to replicate the exact 172.1g reference mass of the authentic manufacture timepiece.
What are the movement specifications for Reference 126713GRNR?
Reference 126713GRNR is powered by the Rolex Manufacture Cal. 3285 - 70h Power Reserve operating at 28,800 vph (4 Hz) with a 72-hour power reserve, regulated across six positions to +0.8 s/d, 300 deg.
What dial and bezel specifications distinguish Rolex GMT-Master II Ref. 126713GRNR?
Reference 126713GRNR combines Hand-Finished Sunray Collector Dial with Hand-Finished Luminous Appliques & Hands and Precision Brushed & Polished 18K Rolesor Bezel with Anti-Reflective Scratch-Resistant Sapphire Crystal within a 40.0 mm x 11.9 mm 18K Gold & 904L Oystersteel Rolesor case weighing 172.1g, verified via Fischer XRF spectroscopy and powered by Rolex Manufacture Cal. 3285 - 70h Power Reserve.
Rolex GMT-Master II Guinness / Zombie Grey & Black Cerachrom Ref. 126713GRNR — XRF Certified Edition
Fischer XRF Verified 18K Gold & 904L Oystersteel Rolesor • Mettler-Toledo 172.1g • Rolex Manufacture Cal. 3285 - 70h Power Reserve
| Assay Specimen ID & Official Reference | Rolex — Oyster Perpetual GMT-Master II | Ref. 126713GRNR | SKU: LAB-CNC-126713GRNR-W139 |
|---|---|
| Fischer XRF Elemental Purity & Alloy | 18K Gold & 904L Oystersteel Rolesor — 5-Axis Swiss CNC Precision Architecture • 1:1 Authentic Reference Mass • Bespoke Collector Commission |
| Mettler-Toledo Gravimetric Mass (g) | 172.1g — 1:1 Authentic Reference Mass Verified on Mettler-Toledo Analytical Scale |
| Bezel Tolerance, Gem-Setting & Case Dimension | Precision Brushed & Polished 18K Rolesor Bezel with Anti-Reflective Scratch-Resistant Sapphire Crystal • 172.1g 18K Gold Rolesor • 40.0 mm x 11.9 mm |
| Calibre Reference & Witschi Chronometry | Rolex Manufacture Cal. 3285 - 70h Power Reserve — Swiss Super Clone Mechanical Calibre Regulated to +0.8 s/d, 300 deg |
| Isochronism Frequency & Autonomous Power Reserve | 72-Hour Power Reserve • 28,800 vph (4 Hz) Free-Sprung Balance Wheel |
| Double AR Sapphire Crystal & Barometric Rating | Scratch-Resistant Sapphire Crystal with Double Anti-Reflective Coating • 100m / 330 ft - Triplock Screw-Down |
| Dial Metallurgy & Clasp Hallmark Verification | 40.0 mm x 11.9 mm • Hand-Finished Sunray Collector Dial with Hand-Finished Luminous Appliques & Hands • Hand-Brushed & Chamfered Integrated Solid Link Bracelet & Deployant Clasp |