Figure 8. First-derivative curves for two types of chlorite, clinochlore (top) and ripidolite (middle), and glauconite (bottom). The clinochlore is from Calaveras, CA and was purchased from Wards Natural Science Establishment. The ripidolite is Clay Mineral Repository sample CCA-2 from El Dorado, CA. Glauconite is from ODP Leg 174, 1072A 27R 1W 005. The analytical wavelength range for the Minolta Spectrophotometer is 400-700 nm and, for the Perkin-Elmer Lambda 6 spectrophotometer, 250-850 nm.