Historically, explanation has been associated with causation: to explain an event or phenomenon is to identify its cause. But with the growth and development of philosophy of science in the 20th century, the concept of explanation began to receive more rigorous and specific analysis.
For jewelry applications, gauges 12-28 are most common. The size of wire is defined by one of two measuring systems. The American wire gauge (AWG) and the Standard wire gauge (SWG) systems.
Not sure if this was ever posted. But here is a comparison chart for Wire Sizes. 28 Guage => .0126 => Medium Size => Waspi. 30 Guage => .010 => Brassie Size => Waspi. 33 Guage => .00708 => Ultra Small Size => Waspi. 38 Guage => .00397 => X-Small Size => Waspi. Most of the colored copper wire in craft stores is 28 Gauge. Other sizes are available on line if you search.