Copper Air Chasing
This forging technique is known as air chasing. Malleable copper is folded in half to form an air pocket. After clamping the edges in a vise, various tools are used to hammer a design into the copper, chasing the indents into the air gap. The copper is then unfolded to reveal the design on the inside, hammered flat, treated and shaped to the desired form for the jewelry piece. Embossing refers to a similar technique in which the piece is hammered on the front side, sinking the metal. The two techniques are often used in conjunction.