  A new BeppoSAX broad-band (0.6-150 keV) spectrum of the Seyfert 2 galaxy Mkn
3 is presented. The spectrum provides a direct measurement of a large, neutral
column of gas with Nh~10**24 cm**-2 in the source direction. The source, as
bright as 3C 273 above 10 keV, has a steep (Gamma~1.8) spectrum without any
evidence of a high-energy cutoff up to at least 150 keV. At lower energies, the
data are best modeled with the addition of an unabsorbed reflection component.
Combining these data with previous Ginga and ASCA observations, the Fe
K$_{\alpha}$ and reflection continuum indicate that the reprocessed emission is
responding slower than the intrinsic continuum variations suggesting a size of
the reprocessor >= 2 pc. Identifying such a reprocessor with a (close to
edge-on) obscuring torus, the overall result fits well into unified models
since, presumably, one can interpret the strong absorption as due to
transmission through the rim of the torus and the unabsorbed (directly viewed)
reflection component as due to reprocessing from the torus inner surface.
