  We present the results of simultaneous XMM-Newton X-ray and 3.5m/CAHA optical
spectroscopic observations of the Seyfert galaxy Mrk 993. This galaxy exhibited
in the past significant variations of its broad emission lines which classified
it as Sy1, Sy1.5 and Sy1.9 in different epochs. In order to test the
X-ray/optical consistency of the unified AGN model we have compared the amount
of photoelectric X-ray absorption with the Balmer decrement of broad emission
line components. The optical data show that during our observations Mrk 993 was
in a Sy1.8 state with a Balmer decrement of 9. The X-ray absorbing gas amounts
only to 7E20 cmE-02, most likely due to the host galaxy. For a normal gas to
dust ratio in the absorbing material (expected to arise in the molecular torus)
both quantities are clearly discrepant with an intrinsic Balmer decrement of
3.4. We therefore conclude that the Balmer ratio is intrinsic rather than
produced by obscuration and therefore that in this object the optical broad
line emission properties are dictated by the physics of the broad line region
rather than orientation/obscuration effects.
