The Argyle Colour Grading System Explained: GIA vs. Argyle Standards
The Argyle colour grading scale is a proprietary 1–9 classification system where 1 represents the deepest, most saturated hue and 9 represents the lightest pastel blush, categorised across Purplish Pink (PP), Pink (P), Pink Rose (PR), Pink Champagne (PC), Blue Violet (BL), and Red.
By Jonathan Evans · 7-minute read
1. The Flaw in the GIA System for Argyle Pinks
Numbers 1 to 9
Grade 1 marks the deepest vivid saturation and 9 marks the softest blush. Tiers 1 to 3 represent investment-grade apex stones.
Letters PP, P, PR & PC
PP denotes Purplish Pink, P is Pure Pink, PR is Pink Rose, PC1–PC3 is Pink Champagne, and BL1–BL3 is Violet-Blue.
Cross-Grading Tiers
GIA "Fancy Intense Pink" aligns broadly with Argyle 3P–4P, while GIA "Fancy Vivid Pink" aligns with apex Argyle 1P–2P and 1PP–2PP.
The Gemological Institute of America (GIA) is an esteemed international body. However, its broad coloured diamond grading system was designed for the entire global diamond market rather than the singular, microscopic nuance of East Kimberley lamproite stones.
The GIA grades diamonds by placing them between wide reference points, allowing a substantial spectrum of saturation variances to cluster under a single broad grade such as "Fancy Pink". When pricing escalates non-linearly with every half-shade of colour depth, this broad categorization leaves significant economic value unmeasured.
2. The Argyle Difference: Closed-Loop Master Stones
The Argyle Pink Diamonds™ grading methodology was an exacting closed-loop process. Mine gemologists in Perth matched each polished diamond directly against a master stone from Rio Tinto's confidential master vault library under standardized North daylight illumination.
With over thirty distinct pink saturation brackets across its hue spectrum compared to just seven in the GIA framework, Argyle colour grading provides the verifiable granularity required by institutional collectors and family offices.
3. The Interactive Argyle Colour & Intensity Chart
The Argyle Colour & Intensity Scale
Purplish Pink
WHITE
9PP
8PP
7PP
6PP
5PP
4PP
3PP
2PP
1PP
Pink
WHITE
9P
8P
7P
6P
5P
4P
3P
2P
1P
Pink Rosé
WHITE
9PR
8PR
7PR
6PR
5PR
4PR
3PR
2PR
1PR
Pink Champagne
PC1
PC2
PC3
Blue Violet
BL1
BL2
BL3
Red
PURPLISH RED
RED
As each Argyle Pink Diamond™ is unique, the images shown are representatives of a range, and the colour will vary within the categories.
4. Secondary Market Valuation & Verification
While a GIA certificate is universally respected for broad market diamonds, the official Argyle Pink Diamonds™ certificate—with its proprietary colour grade and matching girdle laser inscription—remains the gold standard in the secondary market.
Following Rio Tinto's 2020 mine closure and the October 2026 acquisition of the Argyle brand and archival custody by Boodles, original documentation represents an irreplaceable store of provenance that underpins resale liquidity worldwide.