How to Make Rock Salt
Heat some water. Don't use too much water or this won't work. Continue adding salt to the hot water until the water reaches a boiling stage. Once the boiling water reaches the stage where you cannot add more salt, remove the mixture from the stove burner. When the boiling water cannot take any more salt (a saturated solution) take the mixture off the stove and let it cool. The salt will form crystals as the water evaporates. Crush the salt
crystals
You can make a wide variety of shapes and sizes, but remember, the thicker the piece, the longer it will take to fully dry. If you make beads, you need to stick a toothpick or skewer into the bead then remove it before you let the bead dry. Actually, rock salt is not K2SO4; it is NaCl. It can have impurities of gypsum (CaSO4) and sylvite (KCl) but it is very rare to find potassium sulfate as a mineral, although occasionally polyhalite (K2Ca2Mg(SO4)4.2H2O) is found associated with rock salt deposits.
Heat some water. Don't use too much water or this won't work. Continue adding salt to the hot water until the water reaches a boiling stage. Once the boiling water reaches the stage where you cannot add more salt, remove the mixture from the stove burner. When the boiling water cannot take any more salt (a saturated solution) take the mixture off the stove and let it cool. The salt will form crystals as the water evaporates. Crush the salt
crystals
You can make a wide variety of shapes and sizes, but remember, the thicker the piece, the longer it will take to fully dry. If you make beads, you need to stick a toothpick or skewer into the bead then remove it before you let the bead dry. Actually, rock salt is not K2SO4; it is NaCl. It can have impurities of gypsum (CaSO4) and sylvite (KCl) but it is very rare to find potassium sulfate as a mineral, although occasionally polyhalite (K2Ca2Mg(SO4)4.2H2O) is found associated with rock salt deposits.