The Karen occurrence is located south west of Upper Arrow Lake between Mulvehill and Blanket creeks.

The area is underlain by quartzite, quartz arenite sedimentary rocks and calc-silicate metamorphic rocks of the Proterozoic to Lower Paleozoic Monashee Complex. The strata strikes northwest and dips moderately to the northeast.

Locally, radioactivity is associated with a narrow zone of weathered muscovite schist flanked by quartzite. Probable mineralogy is monazite, allanite and euxenite (Assessment Report 11697).

In 1978, a chip sample assayed 0.06 per cent thorium oxide, 0.0036 per cent uranium, 0.36 per cent lanthanum, 0.815 per cent cerium, 0.08 per cent praseodymium, 0.38 per cent neodymium, 0.05 per cent samarium and 0.05 per cent gadolinium (Assessment Report 7232).

In 2005, rock sampling of old pits yielded up to 0.011 per cent uranium, 0.25 per cent lanthanum, 0.54 per cent cerium, 0.23 per cent neodymium and greater than 0.1 per cent thorium (Sample 288467; Assessment Report 28294).

In 1978, Wollex Exploration completed a program of prospecting and rock sampling on the area as the ARCL 1-2 claims. In 1982, Aurun Mines completed a program of rock sampling, geological mapping and a ground radiometric survey on the area as the Karen claim. In 2005, Whistler Gold completed a program of rock sampling and a ground scintillometer survey on the area as the Cranberry Creek property. In 2013 and 2014, the area was prospected as the Mul-Ree and Kar-Ree claims.