Separating device for separating solid particles from liquids and/or gases in production wells, comprising a) a ring stack made of at least three brittle hard annular disks, wherein the top side of the annular disks comprises at least three spacers, which are distributed evenly over the circumference of the disks and the contact area of which is flat so that the spacers have a laminar contact to the bottom side of an adjacent annular disk, and wherein the annular disks are stacked and fixed such that there is a separating gap between the respective individual disks for separating solid particles, and wherein the axial projection of the annular disks on the inner or outer circumference is circular, and wherein the brittle hard material of the annular disks is selected from oxidic and non-oxidic ceramic materials, mixed ceramics made of these materials, ceramic materials with the addition of secondary phases, mixed materials with portions of ceramic or metallic hard materials and with a metallic binder phase, powder-metallurgical materials with hard material phases formed in situ, and ceramic materials reinforced with long and/or short fibers, b) a perforated tube located inside the ring stack, onto which perforated tube are stacked the brittle hard annular disks, c) at least three straps mounted parallel to the axis at regular intervals on the shell surface of the perforated tube located inside the ring stack, onto which straps are slid the annular disks, whereby the annular disks are centered on the perforated tube, and d) an end cap at the top end and an end cap at the bottom end of the ring stack, wherein the end caps (5, 6) are firmly connected to the perforated tube. a) a ring stack made of at least three brittle hard annular disks, wherein the top side of the annular disks comprises at least three spacers, which are distributed evenly over the circumference of the disks and the contact area of which is flat so that the spacers have a laminar contact to the bottom side of an adjacent annular disk, and wherein the annular disks are stacked and fixed such that there is a separating gap between the respective individual disks for separating solid particles, and wherein the axial projection of the annular disks on the inner or outer circumference is circular, and wherein the brittle hard material of the annular disks is selected from oxidic and non-oxidic ceramic materials, mixed ceramics made of these materials, ceramic materials with the addition of secondary phases, mixed materials with portions of ceramic or metallic hard materials and with a metallic binder phase, powder-metallurgical materials with hard material phases formed in situ, and ceramic materials reinforced with long and/or short fibers, b) a perforated tube located inside the ring stack, onto which perforated tube are stacked the brittle hard annular disks, c) at least three straps mounted parallel to the axis at regular intervals on the shell surface of the perforated tube located inside the ring stack, onto which straps are slid the annular disks, whereby the annular disks are centered on the perforated tube, and d) an end cap at the top end and an end cap at the bottom end of the ring stack, wherein the end caps (5, 6) are firmly connected to the perforated tube.