Jeez it's a hot one, as they say around here.
Went for a swim this morning, revelling in the fact that the temperature, 29°, was likely to be as warm as anything we get in Worthing this year. Plus it's autumn here.
I got talking to an elderly lady who was collecting stones off the beach, and she showed me some pumice she'd just picked up. Pumice is cooled lava, but there are no volcanos around here. She said that it had probably come from an undersea eruption off the North Island of New Zealand a couple of years ago.
The next beach along, Denhams Beach, has cliffs at the back whose rock formations bear witness to some serious seismic activity in the past. There are striations going in all directions, with all sorts of different minerals in evidence, sandstone, iron, quartz, basalt, to name but a few, as well as sedimentary deposits (sands and grits) forced into any vacant spaces. According to Wikipedia this seismic activity occurred over the last 500 million years.
I've added a couple of pics (one of which is now my desktop background) to give you an idea. The orange is sandstone, the black iron, the paler colours quartz, and so on.
Australia is a paradise for mineral prospectors; practically the whole country is begging to be exploited for its precious metals and gems. Australia's richest woman Gina Rinehart, a piece of work by all accounts, is the most successful of the plunderers. As a harmless Guardian-reading herbivore, I'm naturally appalled. On the other hand, my iPad wouldn't work without gold, silver, copper, and rare earth metals like niobium, beryllium and neodymium, and then you wouldn't be able to read this. So, I take a nuanced view.