This is my first etching on copper using ferric chloride instead of nitric acid. The ferric bites quite slowly and evenly, but requires a lot of attention because it forms crystals of iron oxide as it bites that have to be removed by feathering, agitation, or by some other means or else they prevent further biting of the lines. The texture in the sky was created by burnishing the entire plate quite hard with a rotary wire brush; this creates a pattern similar to a fingerprint.