Ardownie quarry, Scottish agates
Author: David Anderson
Content by courtesy of : http://www.agatesofscotland.co.uk
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Information about this productive andesite quarry first filtered out in the summer of 1992. It is located immediately north of the Tayside town of Monifieth near Dundee. For a period of 3-4 years it was yielding agates and also geodes of amethyst and smoky quartz.
The agates and geodes were confined to an amygdaloidal horizon exposed in only one section of the south side of the quarry wall. They were of such quality that they easily compared to those from the historic blue hole perhaps even surpassing them in abundance and size. This quarry is, without doubt, the most important Scottish agate locality of recent times.
The rocks of the area around the quarry are predominantly andesitic lavas belonging to the Ochil Volcanic Formation overlain by sandstones of the Lower Devonian age dated at around 400Ma.
The agates were mainly blue/grey and white fortification agates with some up to 200mm with occasionally red/pink agates up to 300mm. The amethyst and smoky quartz geodes were spectacular and were occasionally as large as 300mm.
The agate producing area within the quarry is no longer working and recently no good material has been found. Prior to the quarry being identified as producing agates there is no doubt that many fabulous specimens were fed into the crusher and lost for ever!
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