A grinder, which serves to grind coffee beans, encompassing: - a grinding cone, which has a number of teeth (61, 67), which are spaced apart from one another and which are separated from one another by grinding grooves (60, 66) and which in each case encompass a grinding edge (63, 65) and a first grinding surface (64, 69), which adjoins the grinding edge (63, 65), - a grinding ring, which has a number of teeth (91, 97), which are spaced apart from one another and which are separated from one another by grinding grooves (90, 96) and which in each case encompass a grinding edge (93, 95) and a second grinding surface (94, 99), which adjoins the grinding edge (93, 95), - wherein the grinding cone and the grinding ring are arranged coaxially along a common axis of rotation by forming a grinding slit, which extends between the grinding cone and the grinding ring, - wherein the grinding cone and the grinding ring are configured to be rotated relative to one another about the common axis of rotation, so that, in response to a rotation of the grinding cone relative to the grinding ring, each first grinding surface (64, 69) of the grinding cone is in each case moved in a grinding direction relative to the grinding ring, so as to transport the coffee beans, which are to be ground, from an entrance slit of the grinder in the grinding grooves (60, 66, 90, 96) of the grinding cone and of the grinding ring through the grinding slit to an exit slit, which is arranged below the entrance slit, and to comminute them by means of the first grinding surfaces (64, 69) of the grinding cone, wherein each first grinding surface (64, 69) is arranged such that it defines one of the grinding grooves (60, 66) of the grinding cone at a rear side of the respective grinding groove (60, 66) relative to the grinding direction, - wherein each of the first grinding surfaces (64, 69) of the grinding cone encompasses an angle of inclination φ at an arbitrary point at the respective first grinding surface (64, 69), relative to a tool reference plane (E-I), measured at an assumed working plane (E-II) in the grinding direction of the respective first grinding surface (64, 69), - wherein the tool reference plane (E-I) is a plane in the arbitrary point, which is embodied parallel to the grinding direction and parallel to the common axis of rotation, and wherein - the assumed working plane (E-II) is a plane, which is oriented orthogonally to the axis of rotation and parallel to the grinding direction, through the arbitrary point, characterized in that the angle of inclination φ of at least one of the first grinding surfaces (64, 69) of the grinding cone fulfills the following condition: 90° < φ < 180° - a grinding cone, which has a number of teeth (61, 67), which are spaced apart from one another and which are separated from one another by grinding grooves (60, 66) and which in each case encompass a grinding edge (63, 65) and a first grinding surface (64, 69), which adjoins the grinding edge (63, 65), - a grinding ring, which has a number of teeth (91, 97), which are spaced apart from one another and which are separated from one another by grinding grooves (90, 96) and which in each case encompass a grinding edge (93, 95) and a second grinding surface (94, 99), which adjoins the grinding edge (93, 95), - wherein the grinding cone and the grinding ring are arranged coaxially along a common axis of rotation by forming a grinding slit, which extends between the grinding cone and the grinding ring, - wherein the grinding cone and the grinding ring are configured to be rotated relative to one another about the common axis of rotation, so that, in response to a rotation of the grinding cone relative to the grinding ring, each first grinding surface (64, 69) of the grinding cone is in each case moved in a grinding direction relative to the grinding ring, so as to transport the coffee beans, which are to be ground, from an entrance slit of the grinder in the grinding grooves (60, 66, 90, 96) of the grinding cone and of the grinding ring through the grinding slit to an exit slit, which is arranged below the entrance slit, and to comminute them by means of the first grinding surfaces (64, 69) of the grinding cone, wherein each first grinding surface (64, 69) is arranged such that it defines one of the grinding grooves (60, 66) of the grinding cone at a rear side of the respective grinding groove (60, 66) relative to the grinding direction, - wherein each of the first grinding surfaces (64, 69) of the grinding cone encompasses an angle of inclination φ at an arbitrary point at the respective first grinding surface (64, 69), relative to a tool reference plane (E-I), measured at an assumed working plane (E-II) in the grinding direction of the respective first grinding surface (64, 69), - wherein the tool reference plane (E-I) is a plane in the arbitrary point, which is embodied parallel to the grinding direction and parallel to the common axis of rotation, and wherein - the assumed working plane (E-II) is a plane, which is oriented orthogonally to the axis of rotation and parallel to the grinding direction, through the arbitrary point,