Jewelry wire gauge

A jewelry wire is wire, usually copper, brass, nickel, silver, or gold, used in jewelry making.

Wire is defined today as a single, usually cylindrical, elongated strand of drawn metal. However, when wire was first invented over 2,000 years BC, it was made from gold nuggets pounded into flat sheets, which were then cut into strips. The strips were twisted and then rolled into the round shape we call wire. This early wire, which was used in making jewelry, can be distinguished from modern wire by the spiral line along the wire created by the edges of the sheet.

Modern wire is manufactured in a different process that was discovered in Ancient Rome. In this process, a solid metal cylinder is pulled through a draw plate with holes of a defined size. Thinner sizes of wire are made by pulling wire through successively smaller holes in the draw plate until the desired size is reached.

When wire was first invented, its use was limited to making jewelry. Today, wire is used extensively in many applications including fencing, the electronics industry, electrical distribution, and the making of wire wrapped jewelry.

All metals have a property called hardness, which is the property of the metal that resists bending. Soft metals are pliable and easy to bend while hard metals are stiff and hard to bend. The hardness of metals can be changed by annealing with heat treatment, or by work hardening a wire by bending it.

Since it is made of metal, wire has this same hardness property. 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. A hardness of 4 meant that the wire had been drawn through five or more times and the wire was as stiff and as hard as possible. Most jewelry wire that is sold now is designated dead soft, half-hard, or hard, where dead soft is wire that is manufactured with a hardness of 0, half-hard is wire manufactured with a hardness of 2, and fully hardened wire is wire with a hardness of 4.

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Wikipedia