If you, like me, failed geometry, here is a handy image:
A gauge, in jewelry terms, is the width of the thing you’re wearing. If you have a 14 gauge lip piercing, your jewelry’s diameter is 14 gauge.
If you want a handy dandy guide to gauges you can carry in your wallet or pocket, Bodyartforms includes a business-card-sized version free with any purchase.
So what’s with the weird numbers? 12 gauge? 8 gauge? Well, the system of gauging that we use in the modern body jewelry industry is mainly taken from the American Wire Gauge, created by Joseph Brown and Lucius Sharp, and adopted by the Waterbury Brass Association in 1857.
Brown and Sharp were obsessed with exactness. They spent most of their lives producing ways to measure things and standards by which things should be measured. They literally made things like rulers and micrometers and made them better than anyone else.
Why was it so important to be exacting? Interchangeable parts. Just like you need to be able to buy jewelry and be sure it will fit, clocks and other machines of the 1800s desperately needed standards so that parts made in one place could be shipped to a machinist and fit in their machine.
It became even more important with the advent of electricity, since the gauge of the wire determines the current carrying capacity. Brown and Sharp’s system used precise measurements and geometric reductions to ensure that each gauge produced would be identical. So with their method you make 14 gauge wire in Philadelphia, and it matches the 14 gauge wire in New York.
So why do gauges get smaller as the number gets larger?
Previous wire gauge systems in Europe were popular for centuries before Brown and Sharp came along. The one thing that they each had in common is that they are based on the size of the wire after it has passed through a draw plate.
Medieval wire gauges were thought to be simply the number of times the wire had been run through the plate. So the original size of the wire is 0 gauge, and if you run it through the draw plate, that’s 1 gauge. Run it through again and it’s 2 gauge.
Medieval person 1: I ran it through the draw plate four times.
Medieval person 2: Well, that’s four gauge wire then, innit? But will it fit me nose?
As this handy example indicates, this meant that wire gauges from one shop to the next would be different sizes. Modern gauges are based on geometrical reductions involving equations and such, which will not be shown here, but trust me they exist. Basically, through the miracle of math, a 2 gauge in Idaho is the same as a 2 gauge in New Jersey. As a side note, modern body jewelry tends not to be made in odd gauges, like 1 gauge or 3 gauge. Do not be confused, however, those gauges exist on the scale, they just aren’t often used.
So that is why gauges get smaller as the number gets larger.
FYI, the technique of drawing wire is one of the oldest technologies in the world. Four millennia ago, in ancient Egypt, people were pounding gold out into sheets and cutting off strips to draw through stone beads, which made a hollow tub-like wire. Prior to that, the strips were twisted repeatedly to produce wire with a round shape, but ridged edges.
And because you know you want to know… what’s with shotgun gauges?
Well, back in the day, people measured a cannon’s size by the weight of the iron shot it could fire. A cannon that fired an eight pound shot would be called an eight pound cannon. Fast forward to the era of little cannons you can carry with you, and the lead ball that fits the bore of a 12 gauge shotgun is 1/12 of a pound in weight. The number of balls to the pound is what determines the gauge.
Now you know.