McQueens Valley is on the south side of Banks Peninsula. Agates can be found in situ in the upper reaches of the valley. Unfortunately this involves crawling through dense gorse. As Banks Peninsula was once 3 times higher than present day, it is reasonable to assume that many of the agates found themselves, over time, at Birdlings Flat. Many of the agates found there are similar to the banded grey and white agates found in McQueens Valley.
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