A: Gauge is a measurement of wire thickness with the smaller the number the thicker the wire (Ex. 4 gauge is extremely thick and 34 gauge is extremely fine.) Hardness refers to malleability or stiffness and is typically called “Full-Hard” for extremely stiff wire, “Half-Hard” for stiff wire that is still malleable and “Dead-Soft” for wire that is very easy to bend.
Sample usages in beading and jewelry making:
30 gauge is very fine and often used in wire crochet.
26 and 28 gauge are best used for wire wrapping and delicate wire work.
24 gauge is intended for beads with smaller holes, such as garnet stones and pearls (best used in half-hard to retain some shape)
22 gauge is fairly thick and good for stone and crystals. It can also be used for making your own findings such as eye pins and jump rings. (Can be either dead-soft if you need to manipulate it, especially with your hands, or half-hard if you are looking for more rigidity.)
20 gauge is very thick and good for making clasps. (Consider dead-soft would be best, as this gauge can be difficult to manipulate due to its thickness.)
18 gauge is good for chainmaille or for your heavier-looking pieces.
Dead-soft is the easiest to manipulate with or without tools, but it does not hold its shape well. In the thinner gauges it is used for bead wrapping.
Half-hard will retain its shape better for jump rings and findings, but is not as easy to manipulate, especially in the heavier gauges
Full-hard is very difficult to change its shape without the proper tools or processes
To see a conversion chart for common gauge sizes please click here.