G-Shock’s $80,000 Blue Sapphire Flagship Watch Uses Japanese Joinery Instead of a Single Screw

Back in 2017, G-Shock creator Kikuo Ibe stood on stage at the brand’s 35th anniversary celebration in New York holding a watch that technically shouldn’t even exist. Of course, that watch was a square G-Shock cased in sapphire crystal. It was a stunning prototype with one fatal flaw, in that it couldn’t survive Casio’s own brutal shock testing. Naturally, that meant the watch could never hit the market, and it spent nearly a decade stuck in concept limbo.

Now, with the flagship MR-G line turning 30, the impossible watch is finally real. Meet the G-Shock MRG-D5000 Blue Sapphire.

The Wrong Material for the Job

Sapphire sits at a 9 on the Mohs hardness scale (one notch below diamond), and that makes it practically scratchproof. Of course, the catch here is that hardness and toughness are opposites in materials science, and sapphire shatters under the kind of sharp impacts G-Shocks are quite famous for surviving.

Basically, the company that’s made a name for themselves drop-testing everything it makes when it a completely new direction, choosing the one case material engineered to crack. Casio leaned into the ambitious nature with the project’s internal codename, Blue Rose, which is a nice nod to the flower nature never figured out how to grow on its own.

Not a Single Screw

The breakthrough didn’t come from creating some tougher grade of sapphire. It actually came from ditching fasteners entirely, since drilled screw holes create the stress points where cracks begin in the first place. Instead, the bezel and case are split into multiple hand-finished sapphire components that interlock around a black DLC-coated Grade 5 titanium core. The construction process borrows heavily from kigumi, which is the Japanese carpentry tradition of joining wood without hardware.

The rest of the build is full MR-G flagship treatment. A Gallium Tough Solar module handles radio-controlled timekeeping, the lettering on the face is rendered in 24-karat gold, and the watch retains a proper 200 meters of water resistance. Casio even set another slab of blue sapphire into the titanium caseback, engraved with each piece’s individual serial number.

Dethroning the Golden King

Until now, the most expensive G-Shock ever sold was 2019’s 18-karat solid gold G-D5000-9 Dream Project, which commanded $70,000 across a run of 35 pieces. The MRG-D5000 beats it on both fronts, ringing in at $80,000 with just 20 examples worldwide.

Each one is assembled entirely by hand at Casio’s Yamagata factory before shipping out in a full glass presentation box.

Spec Sheet

Pricing & Availability

The MRG-D5000 Blue Sapphire is priced at $80,000 and limited to 20 pieces worldwide, with a measly six units reaching the U.S. on a staggered schedule between December 2026 and June 2027. If that’s a bit rich, the Blue Rose Project trickles down to the MRGB5000SA ($6,600, limited to 500) and the GMWB5000SB ($770), both landing in November at gshock.com, the G-Shock Soho Store, and select retailers.

Recap

G-Shock MRG-D5000 Blue Sapphire

G-Shock celebrates 30 years of MR-G with its first sapphire-cased watch, a screwless $80,000 flagship limited to just 20 pieces worldwide.