punchmarking

Punchmarking is a method of imprinting symbols or marks on a surface by driving punches, hardened or engraved pins, into the material. The technique produces a series of recessed marks that can form a design, lettering, or serial identifiers. It is used in metalworking, coin production, and labeling, among other applications.

In practice, a punch-marking operation involves placing a blank metal disc or plate on a stable anvil. Each punch bearing a motif or letter is aligned with the surface and struck with a hammer to impart a piercing indentation or raised impression depending on the orientation. The combined marks may be arranged to convey value, origin, or authenticity.

Historically, the term is especially associated with punch-marked coinage in ancient India. From roughly the 6th century BCE to the early centuries CE, coins bore multiple punch marks pressed into the metal rather than being struck from engraved dies. The marks often included symbols such as animals, star shapes, or geometric motifs and were produced by various mints or issuer groups.

In modern practice, punchmarking remains a term used for simple labeling, authentication marks, or decorative work on metal surfaces. It is valued for speed and low equipment cost but may suffer from wear or loss of legibility over time. Alternative methods include engraving, stamping, or laser marking.