Crystals of monazite are generally simple equant to prismatic crystals that show their monoclinic symmetry without any pretense. Twinning is common and produces crosses and angled reentrant crystals. Specimens of monazite are sought after for their unique chemistry, nice monoclinic form and some specimens are actually quite attractive. Color is yellow to brown or orange-brown. Luster is vitreous, resinous or adamantine.
Specimens are translucent to opaque, but small crystals can be transparent.
Crystals are rarely flattened or tabular. Twinning is common forming crosses and variously angled reentrant crystals. Typical habit is granular or massive with no distinct form. Cleavage is perfect in one direction, poor in several other directions. The result is often shards or acutely angled splinters.