They make jewelry pin backs. You can buy a pack for like a dollar at any craft store. They're flat on one side precisely so you can glue it to the back of a brooch.
Founder and President, Madison Area Costuming Society, a chapter of the International Costumer's Guild
Strange Land Costuming - www.strangelandcostumes.com
Director, SF&F Masquerade
- COSTUMECON34 - Madison, Wisconsin - May 6-9, 2016 - www.costumecon34.com