I will share what is needed to make a painting on stone. the materials needed and used are also quite simple and easy to find. You can buy or can use the items that already exist in your house. check out the following required materials !!
Varnish (I favor the paint-on type, yet spray varnish functions fine too).
Mod Podge or Craft Glue.
Stamps and also Archival Inks (optional).