In general, you can use any wire for sculpture wire. If you need wire of a particular color, a certain thickness or with a certain flexibility, then those factors will govern your choice. Pick the kind of wire that fits your budget and provides a level of comfort. Once you have found a suitable wire, you are ready to create not only a base for your sculpture but also the entire work of art.
Contact a local business like the telephone company for wire. Such companies use large quantities of wire and may have scraps left over. Their scraps could produce several wire sculptures and bases; they may be glad to have someone take away the scraps for free. The wire, which may have several colors, will work fine for your base.
You can purchase paddle wire, also known as floral wire, in the floral section of a craft store. Paddle wire is generally a silver color and thin. Examine the label to determine how much wire is in one package. Compare the costs with the quantity. This is the wire florists use the wire to hold their displays.
Go to a hardware store and buy some steel wire. Look for 16-gauge galvanized. Other options include copper wire. Copper changes color when left outside; the reason is the weathering effect. When exposed to a combination of air containing sulfur compounds, sunlight and moisture, copper gradually changes its color to brown, then to a blue green. Just remember your copper base sculpture will weather over time. Another type of wire is soft aluminum. Look for 12 gauge, which is 0.080 inches thick. If you want a thicker wire, pick 9 gauge. The higher the gauge number, the thinner the wire.