I arrived in Riverton yesterday and made my first visit to nearby Gemstone Beach this morning. I met Chrissy there – she’s a local who writes the Tumble and Polish blog. We spent 3 1/2 hours walking down to the Waimeamea River mouth and back. I collected about 70 stones and, furthermore, Chrissy kindly gave me a bag of trace fossil stones she has been collecting for me. There was a stiff breeze and it was about 14 or 15 degrees, so we had to dress appropriately.
On our way back, as we neared the carpark, we had an interesting chat with a woman from near Auckland about the pretty stones on this beach.
Below are 12 of my finds today. I struggled to get good sun for some of these photos so there are occasionally more reflections on them than usual. The first stone is an unusual one, and I am not sure what type it is. But I love its colour and detailed patterns:
A couple of breccia – stones consisting of angular fragments in a fine grained matrix, often the result of tectonic forces crushing a rock (there’s more information on breccia in this Post):
Three stones with compositions revealed in the close-ups:
Three types of stone reasonably common on Gemstone Beach – a pink thulite, a banded argillite, and a trace fossil argillite stone:
This small stone caught my eye because of the black and white in it:
A green quartzite, similar to ones that can be found especially near Timaru:
I was interested to find this last stone – which I think is light-coloured feldspar in basalt – because it helped to confirm for me that the stone I found at Kakanui (the sixth stone found in the morning of 1 March) is of the same type:
The next Post features another Gemstone Beach fossick. The first Post in this Series is here.
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