Study crystals with some surprising properties, or grow your own! When the polished bottom surface of a TV stone is placed upon a printed page, the words can be read through it, giving the appearance of a television screen. If you look at the words on a printed page through a Calcite Crystal, you see double. Pyrite Cubes are cubic specimens of FeS2, formed over 100 million years ago by sulfur reacting with iron. Grow beautiful crystal gardens with Mrs. Stewart's Liquid Bluing, table salt, household ammonia and food coloring. Sometimes called "Popcorn Rocks", gray Dolomite samples grow beautiful white Aragonite crystals when placed in a small bowl of white vinegar. The Rock Candy Crystal Growing Experiment Kit is a scientific experiment you can eat! Crystals grow to full size in just 7 days!