Chert gives little or no decrepitation at all, in contrast to most vein quartz and this can be useful to discriminate between them. The Cosmo Howley and Enterprise are gold mines hosted in proterozoic sediments in NT, Australia and the Victory gold mine is hosted in Archaen greenstones near Kalgoorlie, WA. In each mine the cherts are easily discriminated from the gold bearing quartz veins using decrepitation. In theory, mapping should permit recognition of these sample types, but in practice many misclassifications of the samples have occurred, highlighting the need for a technique such as decrepitation. One sample of ore bearing vein quartz from the Victory mine is included for comparison. Note also the prominent low temperature peak on this sample, caused by CO2 rich inclusions.