ForMatter/Processes/formative/Prong Setting (Tiffany Solitaire)

proc_setting_prong_tiffany

Prong Setting (Tiffany Solitaire)

formative · prong set, claw setting, Tiffany setting, six-prong setting

highlast updated 2026-04-27

The setting style most engagement rings still use — four or six small metal claws ("prongs") that grip the stone's girdle from above, holding it elevated so light can reach the pavilion from all sides. Tiffany & Co. introduced the canonical six-prong solitaire in 1886 as an explicit visual case for diamond brilliance: lift the stone off the metal, let it move light. Less protective than bezel, more visually open, the cultural reference for the engagement-ring form.

Cast or fabricated head with 4 or 6 prongs (also 8 for fancy shapes), prong inner-face cut with a setting bur to match the stone's pavilion + girdle profile. Stone seats into the prong cradle; prongs are then pressed down over the stone's crown with a prong-pusher, burnished to final tip shape, and rounded. Prong tip diameter typically 0.5–0.8 mm. The classic Tiffany solitaire raises the prongs above the gallery so the stone catches light from below the table.

Scale & Tolerance

scale (mm)2 – 30
tolerance (mm)0.05
skillintermediate to advanced — prong contact with each stone facet must be clean; loose contact gives spinning stone, over-pressed prong damages the stone
costlow equipment cost, moderate labor per setting

Equipment

school_shopprong pusher, setting burs, hammer handpiece, gravers
professionalfully-equipped bench, optical microscope, laser welder for re-tipping prongs

Environmental

energy_usevery low
waste_streamminor metal sweeps
consumablesburs

Compatible materials

18k Yellow Gold

14k Yellow Gold

18k White Gold (Palladium-Whitened)

Platinum 950 (Pt950)

Platinum 900 / Iridium 100

Palladium 950 (Pd950)

Citations

url · https://en.wikipedia.org/wiki/Engagement_ring
book · Revere, *Professional Jewelry Making* (Brynmorgen Press, 2011), prong-setting chapter.

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House vocabulary — terms ForMatter uses with intent.

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iridescent (finish): Hue-shifted accent over base. Anodized titanium and niobium, opal, paraíba. Drives PBR defaults: medium metalness, sheen, clearcoat.
lite-PBR: ForMatter's PBR approach — Principled-BSDF starter values per entry, no measured BRDFs, no commercial assets. Honest reasonable defaults from the finish enum, per-entry numeric overrides where you have a real reason.
Live Preview: The Three.js shader ball that replaces the static CSS sphere on entry pages. Same derive_pbr() values, real-time lit, draggable. Optional — toggle in Preferences.
material: What the thing is MADE OF. The first entity. Aluminum 6061, white oak, soda-lime glass.
metallic (finish): Specular highlight, deep shadow rim. Drives PBR defaults: metalness 1, low roughness, IOR 1.45. Polished steel, gold, copper.
PBR: Physically-Based Rendering. The shading model every modern 3D app uses, parameterized by metallic / roughness / IOR / transmission / clearcoat / sheen. ForMatter publishes starter values for every material entry.
Principled BSDF: Blender's name for the consolidated PBR shader. Most other apps ship the same shader under different names (Standard Surface, ShaderGraph, Substance). One node, every output.
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quote: A voice block carrying a verbatim quotation from a living author, with citation. Distinct from a channeled block. Living = quote only; the rule is enforced at the schema layer.
roughness: Microsurface scatter. 0 is mirror-smooth; 1 is fully diffuse. Most real surfaces sit between 0.2 and 0.8.
sphere proxy: ForMatter's visible-character stand-in for every material. CSS-gradient driven by the entry's palette and finish, not a baked render. Honest about being a proxy, scales to six hundred entries cheaply, tweakable in one place.
substitute: A peer material that could fill a similar role. Cross-references render as sphere pills inside an entry — the gallery feeling extends inward.
transmission: How much light passes through. 1 is fully transparent; 0 is opaque. Glass, gemstones, clear plastics carry transmission.
voice block: A versal block where a real authored voice attaches to the material or process. Schema-tagged with status (living / dead) and mode (quote / channeled). Citations always.
woodgrain (finish): Directional sheen with grain ring. Drives PBR defaults: anisotropic 0.6, medium roughness, no metalness. Every wood entry.

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Materials and processes for people who design and make things.

A local-first library of materials, processes, and applications, equal weight, citable everywhere. Part of the renato.design ecosystem — sibling of Plenum, Specimen, Ingenue, gesture, graf, and the Renato Rhino plug-ins. Form and matter, inseparable.

Why this exists

Half of teaching materials is teaching how the material is made into the thing. The standard subscription library was always light on that half. The wedge here isn't better samples or a prettier interface — it's treating Process as a peer entity, not a footnote.

Rules of the house

Citations or it didn't happen. Every property number, every claim, every borrowed register has a traceable source.
Living authors are quoted only. Verbatim or not at all.
Dead authors may be channeled within their philosophy — marked, cited, never impersonated.
Confidence labeled honestly. A senior's low-confidence-with-three-citations beats a freshman's high-confidence-with-none.
Local-first. Works offline, no login, no subscription.

Sister apps

Ingenue — five voices argue about what to build from electronic parts. Where ForMatter teaches what the thing is made of, Ingenue proposes what the thing could be.
Plenum — vehicle codes through the camera, doo-wop register.
Specimen — iOS field-collection for design students.
renato.design — the rest.

Sources

Conway's Material World on raw materials, Lefteri's Making It on processes, Untracht and McCreight on metalsmithing, USDA Forest Products Lab on woods, GIA on gemstones, Schott / CoorsTek / Toray / Owens Corning datasheets, MakeItFrom for verifiable property numbers, ASM Handbook, ISO standards. Voice blocks: Barthes, Yanagi, Benjamin channeled within their philosophy; Lefteri verbatim. All cited.

v0.5 — 2026-04-27 · Phil Renato · renato.design · MIT-licensed code, CC BY-NC research content

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