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How to Grow Alum Crystals
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Stir the alum until no more will dissolve. This means
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Hi, I'm Lisa Nelson for About.com. Today I'm going to show you how to grow crystals at home using alum.You will need:Alum, or hydrated potassium aluminum sulfate, can be found at most grocery stores with the herbs and spices.Fill a small container with hot water. Add a teaspoon of alum powder and stir until dissolved. Continue adding the alum powder one teaspoon at a time, and stir until no more alum powder can be dissolved in the water. This is known as a saturated solution. The water is at its max carrying capacity for the alum.Carefully pour the alum solution into a shallow container. If there is any undissolved alum remaining at the bottom, avoid pouring it into the container.Place the container someplace where it won't be disturbed, and cover it with a paper towel or a large coffee filter. After several hours, small crystals should form at the bottom of the container. Select one of these seed crystals, and dry it using a paper towel.Tie the string around your seed crystal, then tie the other end around the dowel. Prepare a fresh batch of saturated alum solution, like you did before, and pour the solution into a large glass jar. Suspend the seed crystal inside the jar using the dowel, place the jar someplace where it won't be disturbed, and cover it with a paper towel to keep out the dust. After several days, you should have a large alum crystal.I hope you enjoy this project, and for more information, please visit About.com.
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