The Argyle Pink Jubilee
The Argyle Pink Jubilee
A commemorative pink diamond from the world's most celebrated pink-diamond mine
The Argyle Pink Jubilee is a polished pink diamond recovered from the Argyle mine in the East Kimberley region of Western Australia and cut from a rough crystal weighing 12.76 carats. The stone was named in honour of Queen Elizabeth II's Diamond Jubilee in 2012, a deliberate act of commemoration by Rio Tinto, the mine's operator, that placed the gem within a long tradition of naming exceptional diamonds to mark significant events. Although the Argyle Pink Jubilee occupies a notable position in the mine's recorded history as one of the larger gem-quality pink diamonds to emerge from Argyle, its gemmological profile — precise polished weight, cut grade, and formal colour grading — has not been comprehensively published in peer-reviewed gemmological literature, and the stone has not appeared in major international auction records in the manner of the mine's annual tender highlight stones. What is documented, principally through Rio Tinto's own announcements and contemporaneous trade press coverage, is sufficient to establish its significance as a commemorative gemstone of Australian origin and as a representative example of the rare large pinks that the Argyle mine occasionally produced.
The Argyle Mine and the Rarity of Large Pink Diamonds
To appreciate the significance of the Argyle Pink Jubilee, it is necessary to understand the extraordinary position the Argyle mine occupied in the global diamond trade. Located in the Kimberley region of Western Australia and operated commercially from 1983 until its closure in November 2020, Argyle was for most of its operational life the world's largest diamond mine by volume. It was also, and far more importantly for the purposes of this article, the source of approximately 90 per cent of the world's supply of pink diamonds during that period.
Argyle's pinks owe their colour to a mechanism that remains incompletely understood. Unlike most coloured diamonds, whose hues arise from trace chemical impurities — nitrogen for yellow, boron for blue — the pink colour in Argyle diamonds is attributed to plastic deformation of the crystal lattice during the violent geological processes that transported the diamonds to the surface. This deformation creates what gemmologists refer to as graining, visible under magnification as parallel colour planes running through the stone. The colour is, in the terminology of the Gemological Institute of America, a structural colour rather than a chemical one.
The vast majority of Argyle pinks are small: the mine's production was dominated by stones of less than one carat in polished weight, and even quarter-carat and half-carat pinks from Argyle command significant premiums. Stones exceeding five carats in polished weight are genuinely exceptional; stones in the double-digit carat range are extraordinarily rare. It is against this backdrop that a rough crystal of 12.76 carats acquires its meaning. Even accounting for the substantial weight loss inherent in cutting a pink diamond — cutters must follow the grain planes carefully to preserve colour saturation, often accepting lower yield ratios than would be typical for colourless stones — a rough of that size offered the prospect of a polished pink diamond of considerable size by Argyle's standards.
Discovery and Naming
The Argyle Pink Jubilee rough crystal was recovered during the mine's underground operations at the AK1 pipe, the lamproite volcanic pipe that constituted the primary ore body. Rio Tinto announced the stone publicly in 2012, timing the announcement to coincide with the Diamond Jubilee celebrations marking the sixtieth year of Queen Elizabeth II's reign. The naming convention was consistent with a broader tradition at Argyle of assigning names to exceptional stones, particularly those destined for the annual Argyle Pink Diamonds Tender — the invitation-only sale through which the mine's finest pinks were offered each year to a small group of pre-qualified international buyers.
The Jubilee naming also carried commercial logic. By associating the stone with a globally recognised royal milestone, Rio Tinto amplified the stone's narrative value at a moment of considerable international attention. Pink diamonds from Argyle had by 2012 established themselves as among the most sought-after investment-grade gemstones in the world, with tender results regularly setting per-carat records. A commemorative name attached to one of the mine's largest recent pink rough crystals served both as a tribute and as a statement of the mine's continued ability to produce remarkable material.
Gemmological Characteristics
The precise polished weight of the Argyle Pink Jubilee has not been consistently reported across independent gemmological sources, and the stone does not appear to have been submitted for grading reports from the GIA or other major independent laboratories in a manner that has entered the public record. This is not unusual for stones sold through private channels or retained within corporate collections: a number of significant Argyle pinks have been sold privately, with grading documentation remaining confidential between buyer, seller, and laboratory.
What can be stated with confidence, based on the documented rough weight of 12.76 carats, is that the polished stone would have been subject to the same cutting constraints that govern all Argyle pinks. The lamproite-hosted diamonds from Argyle frequently exhibit strong graining, and cutters working with such material must orient the stone to maximise colour while managing the visual impact of grain planes on transparency and brilliance. Yields from pink rough of this type typically range from approximately 25 to 40 per cent of rough weight, depending on the crystal's shape, clarity, and the intensity of the colour planes. On that basis, the polished Argyle Pink Jubilee would be expected to fall in a range broadly consistent with a stone of several carats — significant by any measure for a pink diamond, and exceptional by Argyle's own standards.
Argyle classified its pink diamonds using a proprietary colour grading scale that differed from the GIA's nomenclature. The mine's scale ran from PP (Purplish Pink) through P (Pink) and PR (Pink Rosé) to PC (Pink Champagne), with intensity descriptors — Fancy Light, Fancy, Fancy Intense, Fancy Vivid in GIA terms — applied within each hue category. The most commercially prized colour was Fancy Vivid Pink, or its Argyle equivalent at the top of the P and PP ranges. The colour grade of the Argyle Pink Jubilee has not been definitively published in accessible literature.
Context Within Argyle's Notable Stones
The Argyle Pink Jubilee should be understood within the broader canon of exceptional stones that the mine produced over its operational life. The most celebrated of these were the annual tender highlight stones, each given a name and offered as the centrepiece of that year's invitation-only sale. Among the most documented are the Argyle Violet, a 2.83-carat Fancy Deep Greyish Bluish Violet diamond offered in the 2016 tender and considered the largest known violet diamond of gem quality; and a succession of Fancy Vivid Pink stones that set successive per-carat price records through the 2010s.
The Argyle Pink Jubilee, as a named stone tied to a specific external event rather than to the tender cycle, occupies a slightly different category. It was a commemorative piece as much as a commercial one, and its public profile reflects that dual character: widely noted in trade announcements at the time of its naming, but less thoroughly documented in the gemmological literature that tends to follow stones through grading, sale, and subsequent auction appearances.
The Closure of Argyle and the Stone's Legacy
The Argyle mine ceased production in November 2020 after the underground ore body was exhausted. The closure was a watershed moment for the global pink diamond market. With Argyle no longer producing, the supply of new pink diamonds contracted dramatically, and the prices of existing Argyle pinks — already elevated — rose sharply in anticipation of and following the closure. Stones with documented Argyle provenance, particularly those with Rio Tinto certificates of origin or named stones with traceable histories, acquired an additional premium as the mine passed into history.
In this context, the Argyle Pink Jubilee's status as a named stone with a documented origin story positions it as a piece of mining and gemstone history as well as a gemological object. Its connection to the Diamond Jubilee of 2012 adds a second layer of historical resonance: it links two of the most significant diamond-related events of the early twenty-first century — the reign of a monarch whose title was itself defined by the gem, and the production history of the mine that more than any other shaped the modern market for coloured diamonds.
In the Trade
The Argyle Pink Jubilee has not, as of the available record, appeared at public auction through the major international houses — Christie's, Sotheby's, or Bonhams — in a manner that would provide independently verified sale data. Its current ownership is not publicly documented. This is consistent with the handling of many significant Argyle pinks, which are frequently sold through private treaty to collectors, investment funds, or high-net-worth individuals who prefer discretion. The absence of a public auction record should not be interpreted as diminishing the stone's significance; it reflects, rather, the private character of the market segment in which the finest Argyle pinks have typically traded.
For collectors and researchers seeking to understand the Argyle Pink Jubilee's place in the hierarchy of notable pink diamonds, the most reliable primary sources remain Rio Tinto's own archived press releases from 2012 and contemporaneous coverage in trade publications. Independent gemmological verification of the stone's specifications awaits either a public sale or the voluntary disclosure of laboratory documentation by its owner.