Silver Filled refers to a process whereby silver is mechanically bonded to a copper core to the extent that silver-filled wire is 10% silver by weight. Silver filled is hundreds of times thicker than silver plating but with many of the same properties as solid silver: parts can be soldered, hammered, oxidized, and tumbled. Best of all, it has the same look as solid silver but at a much lower cost. This Silver Filled Wire is dead-soft, making it suitable for most wire wrapping applications. The fill is 99.9% fine silver, which tarnishes less than sterling silver. Each coil is 12.5 ft. (32 cm) long, weighs 1/2 troy ounce (15.55 grams) and is 22 ga. (0.64 mm, 0.025").