Rapper Jay-Z spotted wearing a Richard Mille

Jay-Z was photographed relaxing on vacation aboard a 450-foot, $500 million mega-yacht with wife Beyoncé, and on his wrist sat what may be the single most technically ambitious watch in his formidable collection: a Piece Unique green sapphire Richard Mille RM056 Tourbillon, a commission that pushes the boundaries of what is possible in case construction.

The Richard Mille RM056 debuted in 2012 and immediately rewrote expectations for haute horlogerie. Its defining feature is a case machined entirely from laboratory-grown sapphire crystal — including the middle case, lugs, and movement bridges. Sapphire rates 9 on the Mohs hardness scale, second only to diamond, which makes machining it with the necessary sub-millimeter tolerances an almost prohibitively difficult process. Colorless sapphire versions alone command seven-figure prices; a green sapphire Piece Unique pushes well beyond that threshold. The movement inside is a manual-winding tourbillon caliber with a baseplate and bridges also executed in sapphire, offering a completely unobstructed view of the mechanics from every angle.

Among serious collectors, the RM056 reference occupies a category unto itself. Richard Mille produces only a handful of sapphire-cased pieces per year — the machining process is so exacting and the rejection rate so high that volume production is impossible. Piece Unique commissions like this green variant are negotiated directly with the manufacture and never enter conventional retail channels, meaning provenance and access matter as much as price. The RM056 has consistently appreciated on the secondary market and appears at major auction houses when it surfaces at all.

Jay-Z has long been one of Richard Mille's most prominent celebrity ambassadors, appearing at brand events and building a collection that includes several RM references. His wearing of the RM056 Piece Unique in a deliberately informal setting — on a yacht, on vacation — underscores the Richard Mille philosophy of watches built to be worn, not locked in a safe.

List price for the green sapphire RM056 Piece Unique is reported at approximately £2.1 million, equivalent to roughly $3 million USD. Given its unique status and the current appetite for top-tier Richard Mille references among ultra-high-net-worth collectors, any grey-market valuation would be speculative — but demand consistently outpaces supply across the entire RM056 family.