With PLM the jewellery item is formed layer on layer. A layer of metallic powder is laid on a work surface, a laser beam is guided over the layer by a CNC system (Computer Numerical Control) which, by controlled switch-on and switch-off, fuses certain parts of the layer (corresponding to the solid parts of the item) leaving intact the powder in the areas corresponding to the hollow or external parts. Once the operation has been completed on the first layer of powder, another layer is deposited until the required item is obtained.