This is an ever growing list of stones that need to be sealed with a protective varnish before putting into the copper electroforming bath. Check out this guide on sealing everything from stones to bones to learn how to seal these stones.

  • Amber
  • Ammolite
  • Ammonite
  • Angelite
  • Apatites
  • Apophylites
  • Aragonites
  • Aura Quartz
  • Azurite
  • Bismuth 
  • Calcite
  • Carborundum
  • Celestite
  • Chrysoprase
  • Coral
  • Druzys
  • Hematite
  • Howlite
  • Lapis Lazuli
  • Larimar
  • Malachite
  • Opal
  • Orthoceras
  • Pyrite
  • Rhodochrosite
  • Ruby in Zoisite
  • Serpentine
  • Shungite
  • Spirit Quartz
    (only if it contains iron, usually the orange ones.)
  • Sputniks
  • Tourmaline
  • Turqouise

Any fossils, shells, bones, leaves, twigs, pine cones, etc., etc.

A rule of thumb is any stone that's lower than a 7 on the Mohs Hardness Scale needs to be sealed. Check out my extensive blog post on sealing stones and how to properly do so.