24 gauge (0.51mm) Purple colour - 10 yard spool (9.1m). Non-tarnish brass resembles gold and will retain its finish & shine due to our proprietary non-tarnish coating. Tinned Copper and Bare Copper do not have a tarnish-resistant coating so they will patina, or naturally oxidize and darken with time to provide a vintage look. Stainless Steel is not copper. Choose Grey if looking for stainless steel color in a copper wire. Colors are acid-free and vary per dye lot.