Mooralla, Southern Grampians Shire, Victoria, Australiai

Regional Level Types
Mooralla	- not defined -
Southern Grampians Shire	Shire
Victoria	State
Australia	Country

Since the 1960s smoky quartz 'geodes' have been highly sought after from the designated gem collecting site near Mooralla, near the Grampians in western Victoria. The geodes are formed below the surface in weathered greenish-grey rhyolite, known as the Rocklands Rhyolite, which erupted in the Late Devonian period. Decades of collecting have resulted in a landscape of low dumps, partly filled in pits and holes as deep as six metres in an area where good specimens were once recovered from close to the surface.

The predominantly smoky quartz crystals, very dark brown to black in colour, are noted for their transparency and lustre, and often contain wispy swirls and gas bubbles in fluid inclusions. They are found as simple to complex crystals or groups of crystals up to three or four centimetres across and loose crystals, weathered out of the rhyolite, are common. Most valued are spherical geodes up to 10 centimetres across, with one or more crystals attached to the inside walls of the geode.

The inside walls of the geodes are often lined with small opaque and colourless quartz crystals up to a few millimetres long, and sometimes amethystine to pink or lilac quartz of similar size.

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