Peridot is not a gemstone we would normally associate with the Glen Innes district, which is justly famous for its fine sapphires and a host of other gemstones. However, much of the higher country is covered by flows of olivine basalt and from time to time aggregates of olivine crystals can be found in the rock.
The blue metal (basalt) quarries alongside the Gwydir Highway near Glen Innes are quite extensive and some fine peridot gems have been cut from olivine crystals found here. These two stones weigh in at around 1 carat apiece.
On many occasions people have shown me specimens of a yellowish-green mineral they thought was sapphire. Invariably this was found in a creek immediately below a road bridge or crossing and the basalt used in the road construction has been the source of the olivine.
Now that the quarries are owned by the Glen Innes Severn Council, there may be opportunities to search the quarries or at least the rock piles for some of the good material which must be waiting for keen gem hunters to find.
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