  A perpendicularly biased tuneable 2nd harmonic cavity is being constructed
for use in the Fermilab Booster. The cavity's tuner uses National Magnetics
AL800 garnet as the tuning media. For quality control, the magnetic properties
of the material and the uniformity of the properties within the tuner must be
assessed. We describe two tests which are performed on the rings and on their
corresponding witness samples.
