Run voltage through titanium or niobium in an electrolyte and the surface grows a clear oxide whose thickness shifts the visible color — purple, blue, gold, magenta — without dye. Voltage picks the color, not chemistry. Niobium ano-jewelry, color-shifted titanium watches, body-mod implants.
Anodic oxide on Ti / Nb / Ta in a non-aggressive electrolyte (TSP, dilute phosphoric, or borate buffer). Color comes from thin-film interference: layer thickness ~30–250 nm depending on applied voltage (10–120 V typical). Each ~7 V step shifts color. Reverse-polarity strips and re-grows. No dye involved; surface is hard, biocompatible, drift-free. Niobium yields the broadest color range; titanium is more limited but standard for medical / aerospace markings.
character — iridescent, shifts with viewing angle, smooth, biocompatible.
Aluminum Anodizers Council technical bulletins; ASTM B580 anodic-coating standard.
House vocabulary — terms ForMatter uses with intent.
Materials and processes for people who design and make things.
A local-first library of materials, processes, applications, and finishes — equal weight, citable everywhere, so a student can move from "what is this" toward "what's actually buildable here, now, by me." Part of the renato.design ecosystem — sibling of Plenum, Specimen, Ingenue, gesture, graf, and the Renato Rhino plug-ins. Form and matter, inseparable.
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.
Conway, Lefteri, Forty, Sparke, ASM, GIA. Every voice: Voices.
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