An X-ray mirror furnace is described that has been developed for in si
tu diffraction experiments at a synchrotron source for temperatures up
to 1600 K. It can be used in a reducing as well as in an oxidizing at
mosphere. In this kind of furnace, the sample is located at one focus
of a rotational ellipsoid and heated by the radiation of a halogen lam
p located at the other focus. The furnace has been designed to work on
a four-circle diffractometer with minimum restriction of the setting
angles.