The invention relates to an artificial joint cup (2), in particular a hip joint cup, for implanting in a cavity in a bone. The joint cup (2) is, in particular, substantially in the form of a spherical dome cup, having a convex outer surface (3) and a concave inner surface (4). In addition, the joint cup (2) comprises an outer diameter (OD) and an inner diameter (ID). The ratio of the difference (D) between the outer diameter (OD) and the inner diameter (ID) in relation to the outer diameter (OD) is in a region between 0.5 and 0.07, preferably between 0.3 and 0.075, particularly preferably between 0.2 and 0.1. The invention is characterized in that the joint cup (2) is made of a ceramic material, and the convex outer surface (3) has a micro-structuring.