  The new rare-earth arsenate superconductors are layered, low carrier density
compounds with many similarities to the high-Tc cuprates. An important question
is whether they also exhibit weak-coupling across randomly oriented
grain-boundaries. In this work we show considerable evidence for such
weak-coupling by study of the dependence of magnetization in bulk and powdered
samples. Bulk sample magnetization curves show very little hysteresis while
remanent magnetization shows almost no sample size dependence, even after
powdering. We conclude that these samples exhibit substantial electromagnetic
granularity on a scale approximating the grain size, though we cannot yet
determine whether this is intrinsic or extrinsic.
