This is the craftsman or woman, often referred to as a Goldsmith, that actually makes the body of a piece of jewellery. They fashion the piece for the setter to set stones into, the engraver to engrave, the enameler to enamel and the polisher to polish.
They are the person who follows the original artwork to achieve what the designer wants. As with all craftsmen, they are exceptionally talented artists in their own right and have supreme skills. They have been feted as the most talented of craftspeople for thousands of years.