  We present the results of the analysis of the hard band XMM-Newton spectra of
the luminous, L(2-10keV)~3.4E+45 erg/s, radio-quiet quasar, E1821+643. Two
emission features were observed in the 6-7 keV rest frame band, confirming
previous Chandra detection of these structures. We interpret these features as
two single emission lines, one consistent with the neutral Fe K-alpha line at
6.4 keV and the other most likely due to FeXXVI. If related to the quasar, the
high-energy emission line should originate in highly ionised matter, i.e. the
accretion disc or the clouds of the emission line regions. Alternatively, it
may be related to the intergalactic medium of the rich galaxy cluster in which
E1821+643 is embedded. A composite broad emission line in combination with an
absorption line model, however, also fits the data well. We discuss the
possible physical interpretations of the origin of these features.

Astrophysics