Sodium chloride, or table salt, is not the only substance in the salt category. Baking soda and borax are also salts. You form salts by combining an acid with a base, according to Shodor, a Durham, North Carolina, science education website. Mix various salts with hot water to create supersaturated solutions. As they cool, you can grow icy-looking crystals on twists of wire, seed pods, thistle or teasel heads, and small evergreen branches to make holiday ornaments.
Bend wire or pipe cleaners into stars, snowflakes, spirals or other winter-inspired shapes.
Attach an ornament hook or a paper clip that you have unbent into an "S" shape.
Attach hooks or insert unbent paper clips into seed pods and coil wire around the stem ends of teasel and thistle heads and small evergreen branch cuttings to make hooks for them, as well.
Boil 1 qt. water per jar for each salt solution you wish to make. Pour the boiling water into each jar.
Measure 1/4 cup of each salt listed separately. Include baking soda, which is sodium bicarbonate, borax, which is disodium tetraborate, and Epsom salts.
Add one of the various salts to each jar of hot water, 1 tbsp at a time, until the salt begins to settle, instead of continuing to mix into the liquid. Label each jar so you know which salt it contains. Add food colouring to each jar, if you wish.
Hook one or two ornaments over a pencil, skewer or chopstick, at least 2 inches apart. Place the pencil, skewer or stick over the mouth of one of the jars of salt solution with the ornament completely submerged, without touching the bottom or sides of the jar.
Observe the ornaments every half-hour and photograph the salt crystals as they form. Use your photos to make gift tags, calendars or cards to accompany your salt crystal ornament when given as gifts. Crystals form in two hours to two days, advises Laura Lamond, owner of the homeschool science website, Lemonade.
Remove the ornaments when the solutions cool to room temperature. Hang them where they can continue to dry or leave them in the jars until the solutions evaporate completely. If you leave them, pull the ornaments out of the solution every hour or so to prevent crystals from binding them to the sides or bottom of the jar, or to each other.
Tie gold, silver or metallic cord or curling ribbon to each ornament and hang it as desired from your tree or mantel, or use them as package ties on gifts.
Other methods for growing salt crystals include mixing bluing, a bleaching agent, with ammonia, described at the Mrs. Stewart's Bluing website. Wear wraparound eye protection and chemical-resistant gloves if you choose this method. Ensure adequate ventilation by placing a box fan in a doorway pointing into the room and a second box fan in a window pointing out of the room, or mix the bluing and ammonia outside.
The bluing-and-ammonia method creates toxic fumes and causes severe itching and irritation if the liquid splashes on skin. Flush with water immediately for 15 minutes if this occurs.