Greetings All, As part of this ongoing discussion about igneous rocks, I thought I'd share an exam question with the group. The answers that students provide are fascinating. 2. (10 points) Like many objects in nature, art, and various other taxonomic disciplines, igneous rocks are classified according to certain principles and properties. As such, classification represents an important means of communicating information in an attempt to promote understanding. Give an example of a descriptive classification scheme for igneous rocks, and also a genetic classification scheme. Discuss briefly what the advantages and disadvantages of each one might be. Cheers, Bob Dymek Robert F. Dymek, Ph.D. Professor of Geology Department of Earth & Planetary Sciences Rudolph Hall Washington University St. Louis, MO 63130 314-935-5344 (office) 314-809-2296 (mobile)