Using a variety of files and an awl, Mike carved out the ant and "distressed" the plaque.
The remaining traces of marker were then removed and the surface smoothed down.
Once the headbadge was ready, the patina was applied. This is the stuff that gives the headbadge the look of oxidised copper.
This is a liquid patina goes on blue, but turns rusty-green as it air-dries. The process can be speeded up by putting the patina-covered headbadge in a plastic bag for a few minutes.
As the "oxidation" completed, Mike attached the badge to the headtube and it was done. The process took about 30 minutes total and was pretty exciting to watch. I don't think that many headbadges are carved out freehand anymore, and doing it this way gives them a distinctly hand-made look. A big thank you to Mike for letting me observe and share the process!