Round wire is the least expensive to purchase and the most commonly available. This is because all wire shapes begin as round; for any use, round wire doesn't need to be reshaped, just resized, keeping fabrication costs down.
Round wire is available in all gauges, but those most often used in wire jewelry design are between 28 and 14. Round wire cannot be "twisted" with any visible effect; because it is already round, individually twisting it will only harden the wire.
However, two or more round wires can be twisted together with great success and the results can be used to make bracelets and heavy collars.
The smaller sizes, 28-gauge, 26-gauge, and 24-gauge, in dead soft temper, are great for: executing a Viking Knit chain, which can also be modified into a cabochon pendant frame; crocheting bracelets and necklaces, often adding small beads, pearls, and charms; coiling around larger round wire such as 21-gauge, 20-gauge, or 18-gauge to produce ornate frames for larger focal beads, necklaces, bracelets and earrings, as well as around smaller beads in ring designs.
It can also be used to execute intricate woven and braided patterns, and for wrapping around the delicate tops of briolette crystals and gemstone beads. Small half-hard and medium-hard round wire is also used to make lightweight headpins and to attach pearls and beads with very small holes to larger designs; such as "stringing" pearls on a small wire and then connecting it within a heavier pendant or bracelet frame.
Medium-sized round wire in gauges 21 and 20 is considered a multi-purpose round wire. Both gauges, in either a half-hard or full-hard temper, are the most popular choices when making any style of ear wires, as well as for creating individual jump rings, light-weight hooks and clasps, pins for broaches and to make customized eye and headpins.
In dead soft and medium-hard, both 21-gauge and 20-gauge can be used to form beautifully uniform spirals. All three mentioned tempers of 21-gauge and 20-gauge round wires can be used to make wrapped loops and for links and rosary-style work. Some folks like to make sculpted jewelry pieces and tumbled rock "cages" using dead soft round wire in either 20-gauge or 21-gauge, which is also popular with those who work with wire jigs.
Large round wire, in 18- and 16-gauge, is best used in a dead soft temper because it work-hardens extremely quickly. Most often used to make neck wires, collars, and bracelet frames, large-gauge dead soft wire can be a lot of fun to work with!
Try using a chasing hammer to flatten and harden it, and then use an embossing hammer to add interesting texture like dimples. In this fashion, interesting freeform rings, earrings, and other designs take on a life of their own. These wires can also be used to coil smaller round wire around.
Heavier necklaces and bracelets need clasps and hooks made from 18- or 16-gauge wire, as well as individual jump rings that add strength when attaching handcrafted components together. In half-hard, both of these wires are very tough, have a lot of spring.
Caution is advised when hammering medium hard colored craft wire because often the colored coating can lose its adherence to the base metal, causing chips in the color that are difficult to repair.
The heaviest wire used by wire jewelry artists is usually 14-gauge, and occasionally 12-gauge. In a dead soft temper, the best use for these very large wires is for upper arm bracelets, hair combs and as the base frame for tiaras, crowns and torque styled neck pieces.
Square wire is the preferred choice of those wire artists who execute traditional designs in half-hard and sculpted designs using dead soft. It is created by pulling round wire through a square drawing die. All tempers and gauges of square wire can be twisted to produce a "diamond-cut" effect. (For more information and details about twisting wire, please read "Getting Twisted.")
The smallest square wire that is most often used is 24-gauge. In a half-hard temper, this wire can be used to create about everything that can be made with 21g round wire, but for smaller applications. Choices may include individual tiny jump rings and earring and pendant frames for small cabochons and cut stones. In dead soft, 24-gauge can be used to sculpt settings for very small stones.
Probably the most universal size of half-hard square wire is 22-gauge. In traditional wire jewelry designs, 22-gauge half-hard can be utilized to make about anything from framing cabochons to creating ladies fashion rings.
21-gauge half-hard square wire can be used to make ear wires! Yes, twisted square wire will create an ear wire that is relatively "slipless." This gauge and temper is also good to use when making bracelets, earrings and necklace components as well as for making clasps, hooks and headpins.
Rings for men, such as the classic cabochon ring, come out really well when made with either 21 or 20-gauge square half-hard wire. In dead soft temper, both 20- and 21-gauge are popular for sculpting items like cabochon pendants and earrings and some patterns call for these dead soft gauges in certain ring designs.
Larger gauges of square wire in a half-hard temper, such as 18 and 16, work well for very heavy bracelets and when making a variety of clasps and handmade components that need to be able to handle a lot of stress. In dead soft, they texture well for interesting effects and work-harden quickly.
12- and 14-gauge square wires are very thick and are most often worked with in a dead soft temper to make all manner of arm cuffs, neck wires and torque-like necklaces, as well as the base frames for crowns and tiaras.
Half Round wire in all gauges is basically used as a "wrapping" wire to hold square wire bundles together. In a dead soft, the smaller gauges, 20, 21 and 22, the wire will not be strong enough to hold too many wires together without making lots of wraps. In a half-hard, gauges 20 through 16 can be used in pendant frames, rings, bracelets and necklaces. Half-round wire can also be individually twisted, for a cork-screw look that is interesting in earring designs.
Tip: Because gauges of half-round are half the size of the same gauge in square or round wire, do not combine matching gauges; always choose a larger wrap wire. For example: a bracelet made using 20-gauge square wire will not stay together tightly if a 20-gauge half-round is used for the wraps. Instead, for a 20-gauge project choose an 18-gauge half-round, half-hard as the wrap wire.
Pattern wire is made by milling round wire through a drawing die that presses the metal against a form or pattern, such as vines, flowers or geometric designs. Jewelry making pattern wire in copper, sterling silver and gold-filled can be found in a variety of widths (the distance across the top of the wire) and thicknesses. Large, heavy-gauge pattern wire can be formed into a bracelet or neck collar by itself.
Almost all pattern wire can be combined with half-hard square wire to make bracelets, necklaces and even rings. When choosing to combine pattern wire with square, be sure the thickness of the pattern wire matches the size of the square wire, so one does not pull down or over the other while they are being wrapped together.
Of course, as you are the designer of your projects, this article is not meant to be a definitive guide to wire jewelry creation; rather it is meant to be a sampling of what has, and can be done with the variety of shapes, gauges and tempers of the most popular jewelry wires available today.
If you are just starting out, I hope I have explained some of the questions that may have been confusing you; if you are an experienced wire artist who may be contemplating a new design, these articles may save you some possibly expensive experimentation, or suggest possibilities that may not have occurred to you - yet.
As always, Stay Twisted!!