Hammered copper has a stronger surface strength than flat sheets of copper. This is because the small dents in the copper disperse the weight of any object over a wider area. This should not be seen as a weakness in the metal, but as a strengthening technique that has been in use for hundreds of years.

What is hammered copper?

The tradition of hammering copper is a metalworking tactic used for generations to strengthen the surface area of copper sheets, even before the metal material was used to craft mugs. A ball peen hammer is typically used to form the indentations in hammered copper before the sheet is manipulated into its desired shape.

What happens when copper is hammered?

certain amount of hammering (cold-working), copper becomes brittle, a condition that can be removed as often as necessary by heating the material and plunging it into cold water (quenching). The softening operation is known as annealing, and repeated annealings are necessary if much hammering is required for shaping.