1. High-grade your Reynolds Cup sample to the <2 µm fraction. Follow the flow chart below and the procedures described in lab and Moore and Reynolds (pages 204-225). Samples are also available for testing from the Clay Minerals Society Source Clay Project. Your approach to sample preparation and treatment(s) will be unique, depending upon the composition of the original sample. A bench in the geochemistry laboratory (G&G303) has been reserved for the semester as a work area for this class. Please keep this area clean. If you use glassware, clean it and put it back. Chemicals, ovens, ultra-sonic device, etc. are around the lab.
2. Collect randomly oriented X-ray diffraction patterns for the bulk sample and for the <2 µm fraction. Use the following scan parameters:
Whole rock - random:
Start: 3° 2θ End :70° 2θ Chopper increment: 0.01° 2θ Scan rate: 1° per minute
< 2 µm - oriented:
Start: 2° 2θ End :45° 2θ Chopper increment: 0.02° 2θ Scan rate: 1° per minute
3. For each diffractogram determine the peak positions using what every approach you feel is appropriate (cursor, second derviative, or profile fitting). Pring a hard copy and make electronic file version of graphics.
4. Be prepared to discuss your results in class.