| MadSci Network: Chemistry |
Hello Anita:
Your question is a difficult one to find much information on outside of graduate level college texts. The term Liesegang Rings is used to describe a repetitive pattern seen in nature and look like alternating bands. Geologists often observe banding in crystals and rocks which are caused by alternating precipitation of certain chemical compounds. In theory the alternating banding is caused by repetitive "super saturation" of the liquid rock material where certain chemical compounds in the rock melt spontaneously precipitate out to form a band. This process may continue several times and the resulting rock material (or crystals) exhibit a banding. This texture (liesegang rings) have also been observed and described in human tissues by medical doctors (pathologists). Liesegang Rings are also observed by chemists in a variety of chemical compounds. The administrator for the Mad Scientist webpage did an internet search on the Altavista search engine (altavista.digital.com) and came across the following web page
http://wwwitp.physik.tu-berlin.de/~krug/geol_en.html
which has some more information concerning Liesegang Rings. I hope that this adds to the research that you have already done. If you have any further questions please let me know.
Bob Chesson
Try the links in the MadSci Library for more information on Chemistry.