You can use fire on your copper to create a beautiful array of colors. This tutorial will explain how to use a torch to create a patina for your copper jewelry
Clean your copper.
A natural way to clean copper is to use lemon juice. Soak the copper piece in lemon juice for about 15 to 20 minutes. Rinse the lemon juice off the copper and dry. The copper should now be beautifully clean and shinny again.
To patina your copper, run your torch over your piece as the final step in making your copper jewelry. The copper will go through a series of colors as you apply heat. The copper will turn colors in the following order: gold, orange, pink, purple, dark blue, light blue and, finally, black.
You can create different looks by running the torch in different directions. For example, you can run the torch back and forth or you can waive the torch in circles.
Heat the copper slowly and stop from time to time to check the color. The process is inherently unpredictable so you may not be able to repeat and get the exact same color.
Once you have the look you like place the copper jewelry piece on a glass or heat safe container and put it in the freezer to keep the colors from changing or becoming browned from the natural patina process.