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Hermione Cockburn: So I’ve just come down to the mountain south of where we are, just on the eastern edge of the Colorado Plateau, and this whole area has a long history of uranium mining. And I think what they were mining was a uranium mineral called carnotite, which is characteristically bright yellow. And interestingly, the very first uranium used for the atomic bomb, the development of basically the cold war nuclear arms race, came from this whole area.
So in these kind of little crevices what I’m hoping to find ... Uhhh! Look at that. Can you see this bright yellow sort of precipitate here? And what happens is that hot hydrothermal fluids, that’s basically hot mineralised ground water, circulates through the sandstones concentrating, leeching out and concentrating uranium in these secondary minerals just like this. So this should serve as a brilliant natural source for our cloud chamber to test it.
Kate Humble: Now then, good morning.
Kate: Is this is?
Hermione: This is it.
Kate: Let’s have a look at this. Oh is this what you found yesterday?
Hermione: Yes. So this bright yellow, just this, the bright yellow crust on the rock ...
Hermione: ... that’s the uranium mineral
Hermione: I picked out yesterday, so this is the true test.
Kate: Okay. Now you’re confident that that definitely is a uranium mineral that is definitely radioactive?
Kate: Well this is going to tell us. If it works, if it can work with a natural source.
Hermione: Okay, there you go.
Kate: Let’s see, so you put the alcohol in.
Hermione: The alcohol’s in, it’s on the dry ice.
Hermione: Just might take a minute or so to set up the temperature gradient and start the activity.
Kate: Oh no, no, no, look! Look! It’s instant! It’s working.
Hermione: There you see. Just radiating out from the yellow crust there.
Kate: Wow!! Hermione Cockburn, you have a success on your hands!
Hermione: So I now reckon I can distinguish between any radioactive source and any non-radioactive source.