I found this small stone on a Slope Point beach in September 2024. After photographing it and looking at the images closely, it appeared to have many tiny fossils of some kind in it. This is how it looked that day:
I have tried to identify the small shapes within the stone but have not yet been entirely satisifed with a solution. I recently tumble-polished the stone – the outcome was not as good as I had hoped but the shapes have been clarified significantly. They are amazing! A few of them look like tiny long-stemmed fungi. This is one side of the stone now:
I have been busy lately not only with tumble-polishing but with a small book that I am putting together with Chrissy Lampitt who writes the Tumble and Polish Blog. It’s a kind of our identification guide to Gemstone Beach stones, or at least some of them, and is likely to take some months to complete. So far we have collected photos and text relating to argillite (including banded and spotted varieties), trace fossils, thulite, rhyolite (including ignimbrite), and jasper (including poppy jasper). I’ve just starting looking through my photos for specimens of amygdaloidal stones.
Hi there! Just found your blog, and I love it!
The tiny long-stemmed fungi resemble Rayleigh-Taylor instability. This concept is used to describe various fluid dynamical systems, including when a heavier fluid is suspended above a lighter fluid within a gravitational field. I wonder if it can approximate cooling lava as it forms solid rock.
See this link for images of Rayleigh-Taylor simulations: https://computing.llnl.gov/projects/blast/rayleigh-taylor-instability
I’m going to guess this pebble is/was orbicular rhyolite, an extrusive igneous rock formed by silica-rich volcanic ash. I’d love to hear from a geologist about it. Very beautiful!