Last summer I wrote a series of posts on metal etching to go with the demonstration I was leading at the Metal Clay Artisan Guild in CT's July meeting. Part 1: The Resist, Part 2: The "Salt" Etch, and Part 3: DIY Texture Plates covered the step by step process I use to etch. These posts were geared towards creating texture plates for printing on metal clay.
This past month my advanced jewelry students used this same technique to create these awesome etched copper cuff bracelets. After piercing and etching the copper sheet they used liver of sulfur to create a patina to really bring their etched surfaces out. Finally, the bracelets were finished with a clear coat of Rust-oleum Automotive Clear Coat to seal the surfaces they had created. This is generally what I have students seal their work with when using base metals in jewelry class. It is inexpensive, covers smoothly and maintains the surface they have worked so hard to achieve. It also seems to help protect the skin on those who seem to have some sensitivity to base metals.