Stay-at-Home Day Twenty-Five, Sunday 19 April 2020: Stone Twenty-Five

Stone Twenty-Four.

Stone Twenty-Three.

Stone Twenty-Two.

Stone Twenty-One.

Stone Twenty.

Stone Twenty-Five was found on Gemstone Beach:

Stone Twenty-Five.

One side of Stone Twenty-Five.

Stone Twenty-Five.

Edge of Stone Twenty-Five.

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It has polished very well, which makes it difficult to photograph without a lot of reflection. This is especially so for the side which is more raised. I tried photographing it inside on a light coloured surface, but without much improvement.

One side of Stone Twenty-Five, photo taken inside.

Stone Twenty-Five.

I am unable to identify this stone. It looks to me to be possibly along the gneiss-schist spectrum, but this is a pure guess with little to support it.

Stone Twenty-Five in detail.

Stone Twenty-Five in detail.

Stone Twenty-Five in detail.

Stone Twenty-Five in detail.

Stone Twenty-Five in detail.

Stone Twenty-Five.

Stone Twenty-Five in detail.

Stone Twenty-Five in detail.

Gneiss and schist are common and widely distributed types of metamorphic rock, formed by high temperature and high-pressure metamorphic processes acting on  igneous or sedimentary rocks. Gneiss is coarser grained than schist because it forms at higher temperatures (over 450 degrees C) and pressures than schist.

The next Post in this Series is Stay-at-Home Day Twenty-Six, Monday 20 April 2020: Stone Twenty-Six. The first Post is Stay-at-Home Day One, Thursday 26 March 2020: Stone One. 

Author: tumblestoneblog

Retired Academic, male, living in the New Zealand countryside near Whanganui with his wife as well as Jasper the dog, Fluffy the cat, Dancer and Penny, the horses, and a shed half-full of stones. Email john.tumblestone@gmail.com. View all posts by tumblestoneblog