Electroforming is a metalworking technique where metal is built up layer by layer onto a model or form through an electrochemical process called electrodeposition. This method creates a metal piece that is strong yet lighter than solid-metal jewellery of the same size, making it ideal for statement pieces like a Hasli. 

In jewellery manufacturing, electroforming typically involves applying a conductive coating to a shape (often wax, resin, or another base form) and then immersing it in a metal-containing bath. An electrical current causes metal ions to deposit and accumulate into a dense metal shell, capturing intricate details of the design.