TEACHING OBSERVATION THROUGH MINERALOGY

Like most courses, many approaches can be used to teach mineralogy. At many universities, mineralogy students are taught the use of polarizing microscopes, X-ray diffraction and even the microprobe to identify minerals. While they may be proficient in the modern techniques of mineral identification, they may lack the observational skills to identify minerals without these instruments. Many students have little access to these instruments once they leave school; however, many of them will be called upon to identify minerals and rocks with nothing but a hand lens, jackknife, and possibly some acid. Identifications by geologists in the field, and science teachers or students for casual friends must often be made without laboratory instruments. An introductory course that teaches practical techniques of mineral identification is very beneficial. The following describes the laboratory of a course, similar to one I took at Wisconsin-Oshkosh, that may accomplish this. Emphasis is placed upon the properties used to identify minerals. A tray consists of eight minerals, which the student identifies using common tests (hardness, luster, streak, specific gravity, acid, crystal form and habit). After completing each tray, the student meets with the instructor and defends the identifications and answers questions regarding usage, occurrence and origin. Misidentified minerals stay in the tray until correctly identified (or the semester ends). As the semester progresses samples of greater difficulty are placed in the trays, and the students become proficient in using the determinative tables and descriptions in the text. Students, whether majors or non-majors, tend to be much more receptive to this hands-on method than to a modern mineralogy laboratory in which little emphasis is placed on learning how to use and understand the textbook. It also improves the observational skills of students and demonstrates the scientific method in action.