Things You'll Need
Instructions
Place your soft stones in a small bowl and cover them with sand. Place the bowls in an area free of moisture that stays consistently warm year-round. In a cupboard or shelf in a dry room works well.
Allow your stones to sit in the sand for up to six months. The sand will draw out the moisture in the stones, rendering the stones dry and brittle.
Remove the stones from the sand, gently wiping them down with a soft cloth. Some of the sand may stubbornly cling to the stones. It should crumble away with some rubbing.
Pour acrylic sealer (wood sealer or rock sealer from a hobby supply store) into a second small bowl. Set your stones in the sealer.
Cover the bowl with an airtight lid to keep the sealer liquid. Allow the stones to soak in the sealer for about half the time they dried -- from six weeks to three months.
Gently remove the stones from the acrylic and wipe them down with another soft cloth. Let the stones air dry for about 48 hours. The sealer should harden inside the pores of the stone, making it hard and durable.