Thorium lantern mantels

["Jesse H. Coleman" <radshoals@airnet.net>]

RADSAFERS,

Good news for those of us who used to get camping lantern mantels
containing thorium, to use as check sources for GM counters.

Some years ago the much of the industry switched from Th to
nonradioactive yttrium.  Th mantels were harder to find.

I recently found lantern mantels of 3 brands, manufactured in 3
different countries.  I got all 3 for a quick check.  Results:

"Quick Clip" brand, made in China is as good a check source as the
old types, but be careful of the metal clip in the package, it could
puncture a thin window.

"Coleman" brand, made in USA and "Primus" brand, made in Malta did
not seem to contain Th and gave no response to my GM.

Now I need to go camping to use up my supply of cold mantels.

Jesse Coleman (no relation)

RADSHOALS@AIRNET.NET