I started an Etsy shop to see if there are people who want professionally photo etched copper and brass sheet. They can be cut with scissors, jeweler's saw, disc cutter, etc., to make your own pendants, earrings, decorate boxes, greeting cards, etc.
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They can be oxidized with liver of sulphur. Copper can also be oxidized with JAX products. You can also fill in the etched portions with acrylic, Jaquard powders/paints, mixed with a base, ink, etc. Laurie Jo