CIMRM 2366 - Magical gem with tauroctony on side A and Kabeiros on side B. Hamburg, Germany
Note that there is an error in the Michel bibliography. This item is not CIMRM 2354, which is a red jasper in Florence; this item is green - RP.
Note that the item is intended to leave an impression. The image above is therefore reversed, with Mithras facing left.