BX90: a new diamond anvil cell design for X-ray diffraction and optical measurements.

We present a new design of a universal diamond anvil cell, suitable for different kinds of experimental studies under high pressures. Main features of the cell are an ultimate 90-degrees symmetrical axial opening and high stability, making the presented cell design suitable for a whole range of techniques from optical absorption to single-crystal X-ray diffraction studies, also in combination with external resistive or double-side laser heating. Three examples of the cell applications are provided: a Brillouin scattering of neon, single-crystal X-ray diffraction of α-Cr(2)O(3), and resistivity measurements on the (Mg(0.60)Fe(0.40))(Si(0.63)Al(0.37))O(3) silicate perovskite.