Hello there, hope everybody's fine.
Today I report on a measurement I did some time ago on a sample of Brannerite, from a valley in Piemonte, northerwestern region of Italy.
The sample looked reasonably good, although nothing spectacular, the hot part is the “black stuff” and the red arrow points right there for a reason.
18000 CPM was the response from my Ranger and it was definitely a nice start, this test wasn’t going to be anything particularly hard and I knew already no shield would have been needed.
As usual, while I was recording the background with the GS NaI(Tl) 2’’x2’’ I tested the sample with the PDS 100G first. 538 CPS was roughly ten times the counts I get from the background in that room (the background is of course included in the result because you can’t subtract it with this device). As for the dose-rate at contact, the highest figure I read on the display was 1.26 μSv/h (roughly 0.10 μSv/h of which from the background).
After an accumulation time of one hour, the spectrum itself only reinforced expected peaks from the background. I didn’t check the calibration first and temperature must had been slightly lower than the day I last calibrated because the peaks were all a bit “south” of where they should have been. Anyway, the real spectroscopic measurement was always going to be the one with the NaI(Tl) 2’’x2’’ so I didn’t repeat the measurement with the PDS.
Again, I calibrated with Cs137 plus the very weak, but still measurable, K40 peak from the background formed during the accumulation with the check source. It worked pretty well keeping the calibration good across the spectrum (literally).
In the end it was a 3 hour spectrum with a 24 hour background subtraction. The result is pretty straightforward, no real surprises. The Pb210 peak at 46 keV is not always visible and it’s very welcome, as for the Th234 there were just hints.
As for the quantitative analysis, the sample gave me 727 CPS vs 260 from the background. As usual this result is comparatively lower than that from the PDS, since you can get the sample closer to where the crystal is with the PDS, being a more compact device.
Have a good sunday.
Massimo
Brannerite from Piemonte, Italy.
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Go-Figure
- Posts: 224
- Joined: 04 May 2019, 22:24
Brannerite from Piemonte, Italy.
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Svilen
- Posts: 184
- Joined: 23 Sep 2016, 04:25
Re: Brannerite from Piemonte, Italy.
I learned a new one, thanks :)
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Go-Figure
- Posts: 224
- Joined: 04 May 2019, 22:24
Re: Brannerite from Piemonte, Italy.
This one has been sent to me by a person who's involved with a mineralogy paper on a number of uranium ores samples and he wants to include my spectra in it. This is the first of the two.
The bonus was that, once he got the spectra, he was so happy he told me to keep the ores, so I didn't do it entirely for free :)
Massimo
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Sesselmann
- Posts: 1392
- Joined: 27 Apr 2015, 11:40
Re: Brannerite from Piemonte, Italy.
Massimo,
It is nice to see that your meticulous work is being recognised.
Always a very high standard.
Steven
It is nice to see that your meticulous work is being recognised.
Always a very high standard.
Steven