In examples of fractals such as moon craters,1 rivers,2 cauliflower,3 and bread,4 the actual growth process of the fractal object is missed. In the simple experiment described here, one can observe and record the growth of calcium carbonate crystals — a ubiquitous material found in marble and seashells — in real time. The video frames can be digitized and analyzed to determine the fractal dimension.

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Fractal dimension software can be obtained at http://www.trusoft.netmegs.com. Another option is QuickTime at http://www.apple.com.
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TruSoft International, 204 37th Ave. Rm. N 133, St. Petersburg, FL 33704; 727-894-7426; http://www.trusoft.netmegs.com.
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