Posted by Jeff on June 14, 2010 at 15:15:36:
In Reply to: Polishing a sample for etching posted by Ben on June 10, 2010 at 16:15:18:
The specimen should be polished to a mirror finish. Sounds like you over etched the sample. What is the concentration (strength) of the hydrogen peroxide? Laboratory grade is often 30-35% concentration which will react very fast with the silver. If you've never etched fine silver before, you should use the drug store variety of peroxide which is about 3% concentration. Aternatively you can dilute the stronger concentration with water. Then make the 50/50 mixture with ammonium hydroxide. Swabbing seems to be the easiest to control. A couple of swipes may be all it takes. If you still can't control the results, there are other slower etches.