  Decoherence of massive body wave function under Continuous Spontaneous
Localization is reconsidered. It is shown for homogeneous probes with wave
functions narrow in position and angle that decoherence is a surface effect.
Corresponding new surface integrals are derived as the main result. Probe's
constant density and two completely geometric surface-dependent invariant
tensors encode full dependence of positional and angular decoherence of masses,
irrespective of their microscopic structure. The two surface-tensors offer a
new insight into CSL and a flexible approach to design laboratory test masses.
