By Brent Robillard
Grand Feu
Isotope has never been shy about pushing the boundaries of British watchmaking. Over the past two years, the brand has built a reputation for introducing artisanal techniques—marquetry, cloisonné, guilloché—to a wider audience at a price point that feels daringly accessible. Now, in collaboration with UK-based watch lifestyle platform Oracle Time, the brand takes another step into métiers d’art with the launch of the Mercury Vitreous Green and Orange. These two limited editions, 25 pieces each, celebrate the centuries-old mastery of Grand Feu vitreous enamel while reimagining it in striking, contemporary tones.
Advertisement
Check out the AWAKE Sơn Mài Silver Leaf Collection
Advertisement
Key Features of the Isotope Mercury Vitreous Green & Orange
Enamel dial
Enamel dial making is a craft that stretches back to antiquity, refined in China and eventually perfected by Geneva’s artisans of the seventeenth century. Few materials rival enamel for its luminous depth, but its creation is notoriously unforgiving.
Each dial begins with a textured silver leaf base, layered with enamel powders that must endure multiple firings at temperatures high enough to destroy any imperfection. The result, if it survives, is a dial that feels alive with light and texture—each one unique, each one a miniature masterpiece.
Advertisement
Orange & Green
The Mercury Vitreous Orange lives up to its volcanic name, with a molten dial encased in a 38mm matte black DLC-coated steel case and paired with a black FKM rubber strap. Its counterpart, the Mercury Vitreous Green, offers a cooler interpretation, presenting a spearmint enamel dial within a bead-blasted stainless-steel case, complemented by a grey FKM rubber strap.
Advertisement
Isotope I-7 Calibre
Both watches retain the clean, numeral-free design that has become a signature of the Mercury collection, framed by domed sapphire crystals with anti-reflective coating. Through the exhibition case back, the finely finished Isotope I-7 calibre reveals itself—a regulated and decorated version of the hand-wound ETA Peseux 7001 with a 42-hour power reserve.
A Meeting of Eras
For collectors who followed our hands-on review of the Mercury Shadow earlier this year, these Vitreous editions feel like a natural progression. The Shadow showcased the refined proportions and finishing of the Mercury case, but here enamel artistry takes centre stage, bringing an entirely new layer of vibrancy to the collection’s design language.
Final Thoughts
With the Mercury Vitreous Green and Orange, Isotope and Oracle Time have managed to do something genuinely impressive: honour the legacy of enamel artistry while stripping it of any sense of museum-piece fragility. These watches are meant to be worn, enjoyed, and admired—not locked away. And in that spirit, they stand as some of the boldest expressions of contemporary enamel dial making in recent memory.
Advertisement
Pricing & Availability
Exclusivity is key. Each colourway is limited to just 25 individually numbered pieces, making them as rare as they are beautiful. Pre-orders open on September 15, 2025, at 4:00 pm UK time, with early access available to OT Club members three days earlier. Shipping is scheduled for January 2026, and the price is set at £2,775. As a small bonus, Isotope customers will also receive 50% off OT Club membership with the code ISOTOPE50.
Advertisement
About the author
Brent Robillard is a writer, educator, craftsman, and watch enthusiast. He is the author of four novels. You can follow him on Instagram.
On Spec articles refer to upcoming projects and rely upon available information on Kickstarter, the brand website, and promotional materials provided by the watchmaker. An On Spec article does not preclude a future full-length review in our Off The Cuff section. If you would like your project to feature in On Spec, please contact us here.
Please understand that using any links to products on this site might result in us making money.
One thought on “Oracle Time x Isotope Mercury Vitreous Green & Orange”