Fossil and Petrology collections, New South Wales containing diamond. Many samples in the recent part of the Petrology collection are either irreplaceable or extremely expensive to replace, such as the samples from the Snowy Mountain tunnels or the samples from drill holes. Hand written catalogues from the older parts of the collection are no longer used much because the information has been captured into the ROCKS database. However the old and newer parts of the collection are stored together and are frequently accessed on a day to day basis. There is a potential heritage value for parts of the Petrology Collections and Catalogues. The historical Catalogues could
Pellets (petrology) Pellets (petrology) Pellets are small spherical to ovoid or rod-shaped grains that are common component of many limestones. They are typically 0.03 to 0.3 mm long and composed of carbonate mud (micrite). Their most common size is 0.04 to 0.08 mm. Pellets typically lack any internal structure and are remarkably uniform in size and shape in any single limestone sample. They consist either of aggregated carbonate mud, precipitated calcium carbonate, or a mixture of both. They either are or were composed either of aragonite, calcite, or a mixture of both. Also, pellets composed of either glauconite or phosphorite are common