Autunite mineral

I have just received my latest specimen, Autunite. It is quite fantastic! It is tiny, quite spicy and fluoresces like I have never seen before. The pictures don't do it justice as the colour is strikingly vibrant and has more of a yellow than green fluorescence. I struggled taking photos of it due to the amount of light it produces when it fluoresces. Like trying to take pictures of a light bulb! I took a few pictures with differing light levels. A selection are below. 22,000 CPM on a SBM-20 is quite spicy! Very happy with it.

"Autunite (hydrated calcium uranyl phosphate), with formula Ca(UO₂)₂(PO₄)₂·10–12H₂O, is a yellow-greenish fluorescent phosphate mineral...
...Due to the moderate uranium content of 48.27% it is radioactive and also used as uranium ore"
https://en.wikipedia.org/wiki/Autunite
There are a couple of sellers on ebay at the time of writing with some specimens. Search for 'Autunite'.

 

 

 

 

 

Ah wow, that is an interesting material. That's really quite radioactive too, those close up photos are great! 22.5kCPM!

There was an error in the photo with the Geiger count (so I removed it). The tube conversion factor was out by around a factor of 10 as it was setup for a different tube. What showed as 14.4 uSv/h was in fact 131.4 uSv/h. That's quite spicy!