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

  • Kyanite (rough)

  • 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.