Tumbling
Tumbling is the process of smoothing stones by rolling them around in a container. The club has 4 tumblers - 3 vibrating ones and a barrel one.
Samples of tumbled stones are shown at
http://www.uq.net.au/~zzlstein/gatton/tumbled/tumbled.htm
Stones that have been shaped and then tumbled smooth can be attached to chains to make pendants. Some examples of these can be found at
http://www.uq.net.au/~zzlstein/rocks/rockindex.html