A Glossary of Watch Finishing and Decoration

July 31, 2026

by Andrea, Editor

Marketing speaks in adjectives. A movement speaks in evidence. Between the two sits a loupe, and the vocabulary to read what it shows you.

Every claim a brand makes about its finishing — hand-bevelled, hand-decorated, finished to the highest standard — is either true under magnification or it is not, and the difference is not a matter of opinion. An internal corner is sharp or it is rounded. A bevel throws light in one direction or in several. Geneva stripes meet across a bridge or they stop short at the join. These are legible evidence to anyone who knows.

This glossary collects the terms used across the four preceding articles — the ones you will also meet on auction listings, in service invoices and in dealers’ descriptions, usually in French and usually unexplained.

Each entry says what the technique is, how to tell hand work from machine, and how to separate fine work from ordinary. Where the two are genuinely indistinguishable — and in a few cases they are — it says so plainly, because a glossary that pretends every question has a clean answer is worth less than one that tells you where the real ones lie.

Read it once and the vocabulary becomes yours. After that, a movement`s quality is no longer a mystery. It is a document.

High hand-made quality on a Gerald Genta Ref. 2063

Adoucir — to smooth / satin (preparatory)

What it is. An intermediate step, not a final finish. To adoucir is to take a surface down from rough to even — matte, with a controlled directional grain — in preparation for what follows: anglage, polishing, black polishing or a decorative treatment. It is a stage, not a destination, and on a properly finished movement it should not be the last thing done to any visible surface.

What it tells you. Because it is preparatory, an adouci surface left exposed on a visible component is itself a diagnostic — a sign the finishing was stopped short. Where you expect a polish, a côtes de Genève or a perlage and instead find only an even matte grain, the work has been left incomplete. On hidden surfaces this is normal and correct; on a bridge, a rotor or any face the eye is meant to reach, it is a tell that the movement was finished to a price rather than to a standard.

Grades. The grain should at least be uniform in tone and direction, with no deeper scratches surviving from earlier steps — a clean preparation, even if it is only preparation. A coarse, uneven or scratched adouci surface indicates the work was both incomplete and hurried.

Ajourage — skeletonisation (also squelettage)

What it is. Cutting openings through plates and bridges to reveal the mechanism beneath, without touching the parts that carry the gear train, jewels and screws. The design is drawn before any metal is removed. A skeleton movement (mouvement squelette) is the result carried to its fullest extent, often housed between two sapphire crystals.

Hand vs. machine. Not in the cut — CNC produces cleaner outlines than a hand saw. It is in the walls of the apertures. Hand work files, satins and anglages every wall, with sharp internal corners at each intersection. Machine work usually leaves the walls in the rough.

Grades. Low grade shows saw marks inside the apertures, walls finished only on the visible face, anglage that stops short at difficult corners. High grade is consistent all the way round, including edges that face inward and will be seen by almost nobody.

Industrial quality on a Hamilton jazzmaster

Anglage — chamfering / bevelling

What it is. The filing and polishing of component edges to a bevel, ideally at 45°. Functional in removing burrs, but the single most telling mark of hand finishing. The critical feature is the coin rentrant — the internal corner, where two bevels meet toward the inside of a component.

Hand vs. machine. The internal corner is decisive. A rotary cutter’s diameter always leaves a rounded radius there; a crisp corner with a single clean line at the intersection can only be hand-cut and hand-polished. Machine anglage is clean on straight runs and external corners but rounds off wherever the geometry turns inward. Hand anglage also shows a more hand-made mirror; machine bevels reflect flatly.

Perferct anglage and Flanc on a Lange & Sohne Movement

Grades. Hand: entry-level wavers in width and dulls at the corners; high grade holds constant width through every curve, keeps every internal corner sharp, and polishes the bevel to a mirror. Machine: a milled-and-tumbled bevel is dull and rounded at every edge; better machine work brightens the straight runs, but the rounded internal corners remain the giveaway.

Cerclage — circular brushing / circular satin

What it is. A form of smoothing that leaves fine circular lines and adds brilliance, made by pressing a slate stick or a cabron against a rotating component. Generally reserved for the visible faces of wheels, where it manages reflection as much as it decorates.

“coin rentrant” – Courtesy C. Sernier & G. Papi

Everything is perfect here – Lange & Sohne Cal. L.043.8

Industrial Anglage and Cotes-de-Geneve

Hand vs. machine. Genuinely difficult to call. Both are done against a rotating piece, and a competent machine application is hard to separate from a competent manual one. The diagnostic weight sits entirely in the grades.

Grades. Low grade shows uneven depth, a pattern that fades or smears toward the rim, and a burr where it meets the edge. High grade is even in depth across the whole face and runs cleanly to the boundary. The clearest signal is whether it has been applied at all to wheels the owner will rarely see.

Chassage — pressing / driving-in

What it is. The operation of driving a jewel into its seat. From around 1923 it replaced sertissage(setting), being simpler but demanding a very precise fit of the stone. Setting survives today mainly in the hands of restorers.
Hand vs. machine. A fitting operation rather than a decorative one; not read on a hand/machine axis.

Grades. Not applicable: Quality is read through the jewel seat and its surrounding finish — see chaton and noyure.

Seitz ruby-setting tool

Chaton — jewel setting / chaton

What it is. A metal ring, generally gold or brass, in which a jewel is set. Now largely replaced by direct pressing, but still in use by some prestige makers as a mark of traditional execution.

Hand vs. machine. The presence of gold chatons — screwed or pressed — is itself a deliberate quality decision, not a technique told apart by eye. Note the material: a gold chaton is an unambiguous quality signal; brass or maillechort a little less.

Grades. The presence of a chaton is itself the starting point — it signals a movement built to a higher standard than one with jewels pressed directly into the plate, since the chaton is an added component serving tradition rather than necessity.

Chaton bonanza on a Lange & Sohne movement

From there, quality is read in the execution. Low grade sets the chaton roughly, with an uneven or matte surrounding countersink. High grade seats it flush and true, with a mirror-polished countersink (noyure) framing it and, on the finest work, blued screws holding it in place. Note the material as well: a gold chaton is an unambiguous quality signal, brass or maillechort a more neutral one.

A more basic chaton set up, no retaining screws

Ciselage — chasing

What it is. The opposite of engraving. Where engraving removes metal to create a recess, chasing displaces it to raise a relief, struck with a hammer and a small bevelled steel tool called a ciselet. The ground around the motif is then matted to throw the relief forward. The richly chased balance cocks of the 17th and 18th centuries are the reference.

Hand vs. machine. Hand chasing shows slight variation in relief height and edge definition, and the tool marks of the ciselet under magnification. The industrial equivalent is die striking (coining), which forms the pattern instantaneously — clean, burr-free, and identical across every piece, without individual character.

Grades. Displaced metal work-hardens, so a chaser who overworks an area leaves a dull orange-peel texture, or in the worst case a hairline crack along a raised edge. Low grade softens definition where the design turns and lets the matting thin out in tight spaces. High grade holds crisp edges through every curve, mats the ground evenly throughout, and on the finest work undercuts the relief so the motif casts its own shadow.

CHISELAGE – Courtesy C.Sermier & G.Papi

Colimaçonnage — snailing

What it is. A spiral decoration, applied to ratchet wheels, the flat rims of bridges, oscillating weights, barrels and barrel covers (couvercle de barillet, which typically carries either this or a soleillage). Made with a rotating abrasive wheel oriented to leave a spiral track.

Hand vs. machine. Difficult to distinguish. Both use a wheel against the piece. The grades row carries the diagnosis.

Grades. Low grade shows uneven spiral spacing and depth that varies across the surface. High grade is regular in geometry and consistent in depth from centre to rim.

Poli Miroir (mirror polish) and Colimaçonnage (snailing) on these ratchchet wheels

Côtes de Genève — Geneva stripes / Geneva waves (also vagues de Genève)

What it is. Parallel wavy bands on the visible surfaces of bridges and rotors, named for their sea-wave appearance. Purely decorative.

Hand vs. machine. True côtes are cut on a lathe or straight-line engine, the operator advancing the piece by hand, and the bands align across adjoining bridges at the joins. CNC striping tends to fade in depth toward bridge edges and shows a mechanical regularity without the faint tonal variation of hand work. The most reliable single tell is alignment across separate bridges.

Grades. Hand or lathe: coarse work is broad, shallow and unevenly spaced; fine grade is narrow, evenly pitched and consistent in depth, reading as one continuous field. Machine: basic CNC striping is flat and often misaligns at edges; better machine work deepens the cut and controls the edges but lacks the directional brilliance and cross-bridge continuity of the best lathe work.

Étampage — stamping / pressing (with étampe, the die)

Industrial grade Cotes-de-Geneve and an ETA 2894-2

What it is. A high-precision production method that revolutionised watchmaking by cutting and forming nearly all a watch’s components in large quantities as identical, interchangeable pieces. The étampe is the die that forms, pierces, rectifies and cuts them.

Hand vs. machine. Machine by definition — it is the basis of series production. Stamped parts have no attachment points and present regular edges, acceptable for mid-range; high grade re-finishes the flancs by hand regardless.

Two things to check before rewriting, because the claim as stated is broader than the evidence supports.

The dial-side of a machine-worked movement cal. Valjoux 72C

The movement-side of a machine-worked movement cal. Valjoux 72C

The movement-side of a stamped with minor machine work movement cal. ETA 2834-2

Grades. The dividing line is whether stamping is the finished state or merely the blank. Movements whose bridges, plates and wheels are stamped and left essentially as stamped are cheap movements — the stamping is the part.

Quality movements take a different route: the structural components are machined from solid stock, or, where stamped, are then fully re-worked by hand. Machining from solid is itself the marker of a better class of movement; the finer judgements — flanc preparation, anglage, decoration — then run on top of it. A stamped blank left raw is mid-range at best; the same watch is transformed, or not, by everything done to those surfaces afterward.

A quality machined pallet fork bridge on a vintage IWC Cal. C.83

Rolex 2130 pallet fork bridge, machined

Perfect flancs and anglage on a Lange & Sohne

Flancs — flanks / sides

What it is. The lateral faces of a bridge or plate — the vertical surface between the decorated top and the functional underside. Finishing them is a high-grade requirement beyond mere deburring, because the quality of the anglage depends directly on the quality of the flanc beneath it.

Hand vs. machine. A machined flanc is regular but may show tool marks and, on milled parts, attachment remnants. A hand-finished flanc is drawn flat with files and satined, sharp-edged and free of any waviness — an undulating flanc inevitably produces an undulating bevel.

Grades. Low grade shows tool marks, attachment traces and slight waviness. High grade is perfectly flat and regular with a clean satin and a sharp rise.

A Doré (gilt) finish on a Longines Cal. 13.ZN

Rhodiage (Rhodium plating) and Cotes-de-Geneve on a Vacheron & Constatin

Sablage (sandblasting) on a Breguet La Tradition

Galvanoplastie — electroplating

What it is. Depositing a thin layer of one metal onto another by electrolysis — nickel, gold or rhodium — from 0.1 microns for a flash to 20 microns for a full plating. Protective as well as decorative: brass tarnishes quickly, and plating both preserves and colours it.

Sub-entries: — Dorer (to gild): to cover with gold, generally electrolytically. Plates and bridges are commonly gilded. Gold shades run on a standardised scale from the yellowest (1N) to the reddest (5N).

Rhodiage (rhodium plating): a protective rhodium film giving a bright, hard, non-tarnishing white surface. Standard on high-grade plates and bridges; the reason a well-made 1950s movement can still read crisply white today, where a nickel-plated one has dulled and yellowed.

Sablage (sandblasting / bead-blasting): a fine abrasive jet used to remove burrs and / or produce an even matte surface.

Hand vs. machine. Plating is a bath process, not a hand/machine question. What it reveals is the preparation beneath it: the deposit reproduces the surface faithfully without concealing it.

Grades. Dull patches, scratches showing through the plating, blistering or pooling at edges are not plating faults — they are preparation faults made permanent. High grade begins with a meticulously polished surface, so the plating reads clean and even everywhere.

Génération — gear generation / hobbing

What it is. Cutting wheel teeth with a cutter whose rotation is geared to that of the arbor carrying the wheel blanks, so the tooth form is generated rather than simply stamped.

Hand vs. machine. A machine process. It bears on wheel quality — tooth form, finish and consistency — rather than on decoration.

Grades. Read through the finish of the wheel teeth and crossings: whether the flanks are polished, the crossings chamfered, the faces cerclaged.

Gravure — engraving (with guillocher note)

What it is. Cutting a design or lettering into metal, either as identification (calibre marks, serial numbers, hallmarks) or as decoration on plates, bridges and cases. Hand engraving — gravure en creux, intaglio — cuts directly into the metal with a burin, the design drawn first and then cut entirely by hand.

Hand vs. machine. Several methods, in descending order of hand involvement.

Hand engraving shows directionality — the cut varies in depth with pressure, the metal is polished as it is displaced, and scroll and volute work has an organic quality no machine matches. The traditional pantograph, guided by a template, retains some of that character.

The CNC pantograph and direct CNC engraving produce mechanically uniform depth and spacing with no directionality.

A hand–engraved presentation on a 1930`s Hamilton Rutledge

Laser engraving is geometrically perfect but leaves a thermal signature — discolouration or darkened metal at the cut margins where the beam has burned rather than cut.

Chemical (acid) engraving, the cheapest, leaves rounded, slightly irregular edges and a matte, pitted cut base where the acid has bitten in all directions.

Grades. Hand: coarse work is shallow and hesitant, with uneven line weight; fine grade is confident and even, the metal bright inside the cut.

Machine: read the cut walls — CNC leaves fine rotary tool striations, laser leaves glassy walls with burn at the margins, chemical leaves a matte irregular base. The presence of darkened metal at or in the line is a definitive laser tell.

An Acid Engraved back on a Oris Nordzee

Guillochage — engine turning (with guillocher, to engine-turn, and guillochis, the pattern)

What it is. A geometric decoration of intersecting straight and curved lines cut into metal with a burin guided by a rose engine or straight-line engine, producing patterns of great optical depth. Most often seen on dials.

Hand vs. machine. True guillochage à main is a cutting process on antique hand-operated engines, the operator indexing and advancing each pass; the pattern has organic centre-point geometry and V-profile cuts that catch directional light.

It is distinct from coinage, a stamping process that displaces rather than removes metal, showing rounded channels with slight edge compression, and from CNC milling, which is geometrically perfect but lacks the subtle variation of hand engagement.

Note: at the very top level, a perfectly executed guillochage à main and a perfectly executed CNC guillochage can be difficult to tell apart — the honest answer, in that narrow case, is that its a very difficult call.

Grades. Hand: coarse work shows uneven line spacing and shallow cuts; fine grade is regular in pitch and depth with sharp intersections, brought to brilliance by a final polish. Coined patterns are softer-edged and reflect more diffusely. The blank must be perfectly flat and of even composition, or the pattern distorts — visible as a wander in the lines.

perfect noyure – FP Journe

Noyure — countersink

What it is. A circular recess turned or milled into a plate or bridge to house a component — a screw head, a pinion, or a jewel setting. The first two are functional and left plain; it is the noyure around a jewel that becomes decorative, and that is the one worth reading. Polished, the deep concave form framing the stone is also called découverte.

Hand vs. machine. The recess itself is machined; the distinction is whether it is then hand-polished. A mirror-finished concave countersink is hand work with a wooden peg; a matte or chemically polished one is not.

Grades. Low grade leaves the countersink matte and as-cut. High grade polishes it to a mirror with consistent curvature and a sharp transition to the surrounding surface, giving the jewel visual depth.

Perlage — circular graining / spotting (also perler, to apply it; œil de perdrix, bouchonnage)

What it is. Overlapping small circles applied to base plates, the undersides of bridges, countersinks and sometimes dials. Functional in trapping dust and settling irregularities as well as decorative.

Hand vs. machine. Difficult to call on the circles alone — both hand bench and CNC lower a rotating abrasive peg at intervals. Consistency is read instead: hand perlage on a skilled bench marches in disciplined rows of even size; automated perlage is geometrically perfect and can look mechanical. The weaker tells are at the boundaries, how cleanly the pattern runs to an edge or around an aperture.

Grades. The marker is overlap and size. Low grade shows large circles that merely touch, with gaps of bare metal and uneven depth. High grade shows small, tightly overlapping circles of consistent depth carried evenly across the whole surface, including areas rarely seen.

Poli — polishing

What it is. Bringing a surface to a smooth, bright, reflective finish — the step beyond adouci. In a watch, every part exposed to friction is polished for function; visible parts are polished for appearance. It is the broad category beneath which the specialised finishes sit, poli noir being its most exacting form.

Hand vs. machine. A polish can be raised by hand on a lap or wheel, or by machine, and on a flat bright surface the two can look alike. The distinction shows at the edges and transitions: hand polishing preserves crisp arrises between a polished face and its neighbours, while machine and especially tumble polishing round them over. Rounded, softened edges beside a bright face are the sign of bulk mechanical polishing; sharp edges framing the polish indicate hand work.

Grades. Low grade is bright but uneven, with a slightly wavy reflection and dulled or rounded borders. High grade is flat and clean, the reflection undistorted, the polished area bounded by sharp edges — and, at the top, brought to the dead-flat single-direction reflection of poli noir. A polish that blurs into its neighbouring finishes rather than meeting them at a clean line is the mark of work done to a price.

A plain industrial finish

Poli noir — black polishing / specular polishing

What it is. Not a coating despite the name, but a mechanical polish of hardened steel to such perfect flatness that it reflects light in a single direction — reading black when viewed square-on and white or grey at other angles. The finest of hand finishes, reserved for the visible surfaces of high-grade components: hammers, regulators, contre-pivot plates and above all tourbillon bridges. Rarely encountered on vintage watches; a hallmark of modern haute horlogerie and of the best independent watchmaking.

Hand vs. machine. Effectively a hand discipline. Machine methods — abrasive papers, mechanical lapping — get the surface flat and are excellent preparation, but the true black polish is achieved by working the piece by hand on a zinc or tin plate with diamond paste. No machine delivers the dead-flat, single-direction reflection.

Grades. The test is the optical effect. Anything short of true poli noir — a surface that is bright but reflects in several directions, with the slightest rounding of the angles — is a fine polish but not a black polish. A genuine poli noir is dead flat, without a trace, scratch or stain, and swings from black to white as the piece turns.

Sertissage — stone setting

What it is. The older method of securing a jewel in the movement, in which the metal around the seat is worked to grip the stone — as against chassage, the friction-pressing that largely replaced it from around 1923. Sertissage demands more skill and time than chassage and is now rarely seen outside restoration work, where a period movement may need a setting reproduced in the original manner.

Hand vs. machine. A hand operation, and on vintage watches the only method used before the changeover. Its presence on an early movement is period-correct; its presence on a piece that should carry pressed chatons would be a sign of later intervention.

Grades. Read through the result rather than the act: a clean, even bezel of metal gripping the stone with no distortion to the surrounding surface is good work; a torn or uneven seat, or collateral marks on the plate, is not. On a restored vintage piece, sympathetic re-setting that matches the original technique is worth more than a modern chaton dropped in for convenience.

Courtesy Bersenti.com.png

Soleillage — sunray (movements, rotors) / sunburst (dials)

What it is. Straight lines radiating from a single centre, giving the surface the look of a sun. Made with a bell-shaped wheel turning counter to the piece, oriented so every line passes through the same point. Seen on dials, rotors and barrel covers.

Hand vs. machine. Difficult to distinguish in general; both use a wheel against the piece. The one place to look is the convergence point, where any inconsistency in the tool’s orientation shows first.

Grades. Low grade shows uneven ray spacing and a messy or off-centre convergence. High grade radiates evenly from a clean centre, with consistent depth from centre to rim.

Sunray dial on a Vacheron & Constantin

Materials and Tools

A brief reference to terms that appear in the descriptions above but are substances or instruments rather than techniques.

Materials

Acier – Steel

Used for the working parts that must resist wear and hold a temper — escapement, springs, screws, arbors, pivots — and, from the 1930s, increasingly for cases. Carbon steel is hardened by quenching (trempe) and tempered (revenu) to the required hardness or springiness, and blued by controlled heating.

Stainless steel reached watch cases only in the 1930s, later than one might expect, because early stainless was too hard to machine into small accurate parts. Because the alloy was novel and prestigious, it was marketed under proprietary trade names stamped on period casebacks:

Staybrite, developed at Brown Firth in Sheffield and marketed from 1924; a deep-drawing grade pioneered in Geneva by Taubert & Fils could be pressed into a case without cracking. Protected by Swiss patent from 1930 and licensed on strict terms, it appears as Acier Staybrite inside Rolex, IWC, Omega, Jaeger-LeCoultre, Eterna and Mido, among others.

— Enversteel, Universal Genève’s own trade name for the early stainless alloy used on its cases from the late 1930s through the 1950s. An Enversteel stamp on a UG caseback is a positive period and originality marker.

— Nirosta, Krupp’s German trade name for stainless, used widely across industry and occasionally seen on watch cases.

Acier inoxydable is simply French for stainless steel — the generic, not a brand.

Laiton — brass. The copper-zinc alloy of plates, bridges and wheels; gilded or plated because it tarnishes readily.

Brunissoir - Courtesy FHH

burins pour decolletage

Maillechort — nickel silver / German silver. Copper, zinc and nickel — also sold under the names argentan, alpacca and Neusilber. Harder and less prone to oxidation than brass, and left ungilded on many German and high-grade movements, where it ages to a warm patina.

Rubis — jewel / ruby. Synthetic corundum, the hard bearing at the pivots and escapement; the count is a rough guide to a movement’s complexity, not its quality.

Tools

Brunissoir — burnisher

What it is. A polishing han tool of very hard steel with no teeth, used to bring a surface to a shine by compressing rather than cutting the metal. The tool behind the burnishing (brunissage, also roulage) step in hand anglage and pivot finishing.

Burin — graver A rod of very hard tempered steel, generally rectangular, ground obliquely at one end and sharpened on an oil-stone. The engraver’s and guillocheur’s primary cutting tool. Each craftsman keeps an assortment shaped to their own hand.

Cabron — abrasive lap / dresser

A small stick or lap charged with abrasive, used to smooth and unify a surface through progressively finer grades. A workhorse of hand finishing, used in adoucissage, anglage and cerclage.

Gouge — a hollow, channel-shaped cutting tool for curved recesses.

Grattoir — scraper. A sharp-bladed tool used to brighten a surface where a file cannot reach.

Brucelles — tweezers. The watchmaker’s tool for handling small components.

Archet — bow. A bow, usually wood, strung with a cord, used historically to drive a turn or drill.

Lapidaire — lapidary wheel. A tool for polishing sharp edges on watch cases and bracelets

Cabrons

Tweezers – Courtesy Bergeon

Double Lapidaire – Courtesy Creviosier