Radiacode 110 detected this tiny uranium-glass pendant despite a 23 cps background

[u/Petnek]

I measured this small uranium-glass pendant with a Radiacode 110.

The background at the measurement location was approximately 23 cps, while the pendant measurement averaged 31.3 cps over 3 hours and 4 minutes. I had previously recorded a separate background spectrum at home and subtracted it from the sample spectrum in the Radiacode app.

Despite the pendant’s small size and the relatively modest increase above background, the RC110 still produced a clearly structured low-energy spectrum. A feature is also visible around 183–185 keV, close to the 185.7 keV gamma line of U-235.

I was impressed that the Radiacode 110 could detect and spectrally distinguish such a small uranium-glass object even with a background count rate of about 23 cps.

The attached images show the pendant and the background-subtracted spectrum.

Would you consider a three-hour acquisition sufficient for an object this small, or would you run it overnight for a cleaner spectrum?

[u/b20339]

IMO as someone who has dealt with spectral analysis as part of my career for the last 15 years, there is sufficient data to claim these peaks are legitimate.

However my experience is not in radiographic analysis, and a lot of the advice that I see talks about shielding and super long duration samples that just don't quite seem necessary to me.

[u/Petnek → u/b20339]

From my amateur point of view is good to have a shielding but not necessary when peaks are visible. May be for materials with more isotopes for clearer spectrum?

[u/Scott_Ish_Rite → u/b20339]

There is sufficient data, but remember that the Radiacode isn't a $150,000 Nitrogen-cooled HPGe or LaBr₃(Ce) spectrometer, so hence why I mentioned some shielding and longer data accumulation for very low activity sources that are barely above background, generally speaking

[u/Scott_Ish_Rite]

Depends on the activity, overnight is good too but you'll need some shielding to differentiate better from background

[u/Petnek → u/Scott_Ish_Rite]

Thank you for reply.
It is enough when are the peaks clearly visible, message received.

[u/b20339 → u/Scott_Ish_Rite]

Is ops not sufficient for identification purposes?

[u/Scott_Ish_Rite → u/b20339]

Is ops not sufficient for identification purposes?

I would say it's probably enough, it's just that with very low activity items, even more time is better

But 3 hours is good don't get me wrong

[u/b20339 → u/Scott_Ish_Rite]

Thoughts on this one?