Argyle Colour Grading & The Four Certificate Tiers Explained
Two pink diamonds of the exact same carat weight and clarity can trade at a 300% price difference depending on their Argyle colour saturation number and their provenance certificate tier. Here is how professional valuers read both.
Part 1: The Four Provenance & Certificate Tiers
Argyle Tender Hero Stones
The 50 to 70 finest stones sold annually via sealed bid between 1984 and 2021. Accompanied by a numbered Collector Tender Book, original box, and laser-inscribed Argyle Lot number.
Argyle Certified™ (≥ 0.08ct)
Polished and graded directly by Argyle Pink Diamonds™ (`0.08ct` and above), featuring a microscopic laser-inscribed Lot number on the girdle and tamper-proof Argyle Certificate (e.g., Vault Lots #366392 and #407595).
Argyle Origin (GSL / IGI)
Rough or sub-0.08ct parcels sold directly from the Argyle mine to Authorized Partners and certified by Gem Studies Laboratory (GSL) or IGI with documented Argyle mine origin (e.g., Vault Lot #379804 / GSL #66933/10).
GIA Colored Diamond Report
Graded by the Gemological Institute of America (Fancy Light, Fancy, Fancy Intense, Fancy Vivid, Fancy Deep). Many major Argyle stones carry dual certification (both an Argyle Lot Certificate and a GIA Grading Report).
Part 2: How to Read an Argyle Colour Code (Hue + Intensity)
Because GIA’s broad terms ("Fancy Intense Pink") span a wide visual range, Rio Tinto created a more granular matrix combining a Hue Code with a Saturation Number (1 to 8):
| Argyle Code | Dominant Hue Family | Intensity Scale | GIA Equivalent Range | Registry Link |
|---|---|---|---|---|
| PP (Purplish Pink) | Pink with a cool, electric purple modifier (most prized alongside pure Red) | 1PP (Vivid) → 8PP (Light) |
Fancy Vivid to Fancy Light Purplish Pink | View PP Lots → |
| P (Pure Pink) | Pure classic rose-pink with zero secondary hue modifier | 1P (Vivid) → 8P (Light) |
Fancy Vivid to Fancy Light Pink | View P Lots → |
| PR (Pink Rose) | Warm, rich crimson-rose undertone | 1PR (Vivid) → 8PR (Light) |
Fancy Deep / Intense Pink | View PR Lots → |
| PC (Pink Champagne) | Warm amber/champagne base with a rose-pink overtone | PC1 (Light) → PC3 (Dark) |
Fancy Brownish Pink / Pinkish Brown | View PC Lots → |
| BL (Blue / Violet) | Natural Argyle greyish-blue to deep violet ("Blue Moon" family) | BL1 (Light) → BL3+ (Deep) |
Fancy Greyish Blue / Fancy Grey-Violet | View BL Lots → |