 Most modern manufacturers of jewelry wire make the wire with a defined hardness, generally a hardness of 0, 1, 2, 3, or 4.Historically, these numbers were associated with the number of times that the wire was pulled through a draw plate, becoming harder or stiffer each time it was drawn through the drawplate.A hardness of 0 meant that the wire had been drawn through only once and was as soft and as pliable as possible.