Third Rock from the Sun

This rather dark image does not in fact reflect my mood today, quite the opposite.

It's a simple piece of stone, slate, shale picked up on a local beach a few years ago. I can sit and look at something like this for ages trying to get my head around what occurred millenia back. This was once silt suspended in water. Successive layers of alluvium, if that's the correct term, were layed down by successive tides. These layers hardened, were compressed........... then where does the story go?

I'm no geologist as I've just proved above, yet I find the construction and dynamics of this rock (3rd from the Sun) to be a source of constant wonder. Had I left this on the beach, it would, in time, have become yet another grain of sand.