Found this great article, Make Sure to Do the Math When Selling Your Crafts. It explains different ways to achieve the best bottom line for your arts or crafts business.
An important first step when deciding whether to go ahead with an arts or crafts business idea, is whether you'll turn a profit. Breakeven point analysis helps you make this determination as breakeven point shows you how much you'll need to sell at a certain price to cover your costs.
While doing some online research, I found two great resources for those working in metal - particularly copper:
Whimsie - sells recycled copper sheet
Basic Cooper - sells patina, sheets and other copper supplies
After you purchase some cooper sheet, check out my articles about using a dapping block to shape your sheet.
Unless you are already a Society of North American Goldsmith (SNAG) member, this may be too short a deadline but certainly keep it in mind for next year - SNAG issues it's call for entries for its 2nd UNIQUES online auction. The deadline is April 12, 2014, accepting 40 entries.
Acceptable entries are one-of-a-kind, limited edition, unusual, and handmade contemporary art jewelry and small metal items. Taking place on eBay in order to enter you have to be a SNAG member and submit an object with a retail price of up to $300 each. You receive 50% of the sale.
Ranger Inks has some great products that can help you add patina to your metal working. Available at Hobby Lobby and online at the Ranger Ink website, these inks are relatively easy and safe to use. Set with a heat tool for a lasting finish.