Baryte BaSO4 Thin tabular baryte crystals in leaf like aggregates Size: 20 cm Baryte Desert Rose Sandstone concretion - a rosette aggregate of platy baryte crystals enclosing red sand grains Size: 25cm Calcite CaCO3 A variety of calcite, called dogtooth spar, consisting of groupings of scalenohedral crystals resembling a dog's canine teeth Size: 11cm Calcite Sand Crystals Sandstone concretion where a cement of scalenohedral calcite crystals enclose sand grains Sample Size: 15cm (bottom)