This silcrete seed-grinding dish is from southwestern Queensland. The dish was made by hammerdressing and is heavily worn. The artefact is probably less than 2000 year old.
The deep grooves on both face of this grinding dish were created by attrition during seed grinding. Twin-grooved grinding dishes appear to be more region-specific than the more common single-grooved dishes. The different morphology may have been related to the types of seeds processed on the dish, or perhaps the gesture used in grinding. The grooves on this dish are very deep relative to their width, and are almost V-shaped in profile, but with rounded bottoms. The top-stones used with these grinding stones have an angular morphology that matches the profile of the grooves. This grinding stone is made from a relatively soft silcrete with large quartz pebble inclusions. It was shaped by a heavy hammerdressing (pecking) technique, resulting in large pits.
Grinding dishes like this were critical tools for subsisting in the arid zone of Australia during the Holocene period. Aboriginal people used them to grind native grass seeds into flour. Grinding dishes were often made at quarries associated with sacred storylines, and the stones were extensively traded throughout the arid zone.