We have been experimenting extensively with the sediment disaggregation method of Triplehorn_(2002) using dimethyl sulfoxide (DMSO), which appears to selectively dissolve kaolinite. We’ve found that this treatment works remarkably well for disaggregating many weakly to significantly indurated volcanic tuff samples. Our treatment process involves placing cm- to dm-sized pieces of dry sample in a large glass beaker with enough DMSO to soak the sample, and leaving covered with a watch-glass on a hot plate at ~50°C in a fume hood for 2-3 days. The excess DMSO is decanted and filtered for reuse, and the sample is then rinsed thoroughly with ethanol. At this point the sample tends to fall apart, and can then be moved on to homogenization with a blender and treatment in our ultrasonic horn clay rinsing assembly.