The making
How a stone becomes a dial.
A stone dial is cut, not printed. Between the quarry and the wrist stand five operations, each of which can end a blank that took millions of years to form.
The five operations
Selecting
Every dial begins as a rough specimen chosen for its face: the banding, the veining, the way the pattern will sit inside a small circle. Most candidates are rejected before a saw ever touches them.
Sawing
The stone is cut oversize with a thin diamond blade, slowly and wet. Heat is the enemy: it opens fractures in carbonates and drives the water out of opal. A slice destined for a dial starts several times thicker than it will end.
Backing
A slice under a millimetre has no business surviving on its own. It is laminated to a brass backing plate, which carries the mechanical load, takes the dial feet, and sets the final colour depth of translucent stones.
Lapping
The bonded slice is ground flat between rotating plates with successively finer abrasive, approaching final thickness in passes. This is where most blanks die: a cleavage plane parts, a pyrite grain plucks out, a vein lets go.
Finishing
The survivors are polished until the surface itself is the ornament, then drilled and cut for hands and apertures without disturbing the face. What remains is a section of geological time, sized for a wrist.
What each stone demands
Ten stones, ten temperaments.
- Meteorite01
- A metal rather than a true stone, so the blank survives slicing, the demands lie elsewhere: each slice is acid-etched to raise the Widmanstätten figure, then sealed against rust, and the pattern shifts with every angle of cut.
- Lapis lazuli02
- A rock of three minerals, hard lazurite, soft calcite, brittle pyrite, that cuts and polishes unevenly at dial thinness; many blanks crack during slicing, which is part of why true lapis dials stay rare.
- Malachite03
- One of the softest dial stones, built of alternating harder and softer bands that want to flake apart; it is sawn and lapped slowly, wet, and bonded to a backing plate before final thinning.
- Onyx04
- At dial thinness onyx behaves like dark glass: hard enough for a mirror polish, but brittle, with no cleavage plane to guide a cut, blanks are sawn oversize with diamond tools and lapped down slowly.
- Marble05
- Soft calcite with veins that act as built-in weakness planes: the slice is cut oversize, laminated to a brass backing and stabilised before being thinned to final gauge.
- Turquoise06
- Porous and low in toughness, closer to dense chalk than to quartz. A dial slice is lapped wet at low speed and bonded to a rigid backing to survive; the matrix veining decides each dial’s character.
- Carnelian07
- No cleavage planes, an advantage, but a thin slice is brittle and faintly translucent, so it is diamond-sawn oversize, lapped dead flat, and mounted over an opaque backing that sets its final depth of colour.
- Rhodochrosite08
- Among the most demanding dial stones: soft, with perfect cleavage in three directions, so a slice can part under saw pressure. Cut slow, wet, oversize, and expect to lose blanks.
- Tiger’s eye09
- A fibrous composite whose fibre boundaries are weak planes: the blank is sawn with the fibre direction deliberately oriented, so the chatoyant band sweeps across the finished dial rather than hiding at its edge.
- Opal10
- The most demanding stone in the set: three to twenty per cent water by weight, and losing it means crazing, an irreversible web of fine cracks. The wafer is cut slowly, kept cool and wet throughout, and never subjected to heat.
Thicknesses and methods describe how HAS intends to work; where a stone has a documented industry practice, the notes follow it.
The hardness ledger
Most of what gets cut will crack.
Here is why, in numbers.
The same hardness as carnelian; brittle all the same.
Hard enough to polish like glass, and to stay that way.
Quartz-hard; the fibres, not the hardness, are the risk.
Hard is not tough: opal scratches slowly and cracks quickly.
Three minerals, three hardnesses, one slice.
The number overstates it; porosity is the real story.
A metal among stones: it dents, it never shatters.
Softer than a pocket knife. Handled accordingly.
Barely harder than a fingernail. The hardest cut of the ten.
A fingernail is 2.5. Marble is 3. Respect follows.
Mohs scale, 1-10. Diamond is 10; a steel blade about 5.5; a fingernail 2.5.
What comes with the piece
The watch
Nº of 10, with its provenance name engraved in the record if not the metal. That decision is still on the bench.
The offcut
Every dial is cut from a specific slab. The owner of a piece receives the sealed, tagged remnant of that exact cut, the rest of the stone their dial came from. No two exist, and we could not fake one if we tried.
The extract
A written extract from the register, and the standing promise of a fresh one to any future owner, indefinitely.