CAST IRON / CIRCLE / STREET SURFACE
Medallion Index
Round covers, radial forms, borders, lettering, and the graphic logic of cast-iron circles.
Visual principle
Treat cast iron as urban graphic design: circle, border, embossing, repetition, rust, and pavement contrast rather than infrastructure instruction.
What to notice
Look at radial marks, check patterns, raised lettering, worn edges, rain-darkened metal, and the boundary between cover and street surface.
Editorial use
Use one strong circular image as the anchor, then alternate detail crops and wider pavement context.