MATERIALS
The materials used in the study were Conquest
grade Wyoming bentonite supplied by Colin Stewart MinChem, and Knapton Quarry sand. Conquest
grade Wyoming bentonite originates from New-
castle, Wyoming, and is ground, dried and air
classified during processing. X-ray diffraction spectroscopy and chemical analysis
(Mollins et al.,1996) indicate that it is predominantly a sodium
montmorillonite with some quartz and trace cristobalite. Knapton Quarry sand is a slightly silty, fine,angular quartz sand (containing some iron oxidesand silicate minerals). It was sieved to remove particles greater than 2 mm (the fraction removed represented less than 1% by weight). Other properties of these materials are given in Table 1.