We report He-3 and He-4 sorption isotherms on C60/C70 Fullerene polycr
ystals. The temperature ranges are for He-3, from 1.55K to 3.37K and,
for He-4, from 1.5K to 4.14K. The results give strong evidence that bo
th of the isotopes intercalate into the Fullerene crystal. This opens
up the possibility to study the property of 3D quantum fluid confined
in this way.