I have been up all night fixing this, because when I soldered the sterling silver silhouette to the brass oval and put it in the pickle, I didn't know that there were some copper ions in there, as well, and they got plated onto the brass. Blargh.
That being said, three hours in a hydrogen peroxide/white vinegar solution lifted the plating, and added a really nifty sparkly etched effect to the brass.
Silhouette outline courtesy of Girl-on-the-Moon
Now available at my Etsy store