An artificial masonry unit suitable for use with a panel made of a compressible material having masonry unit receiving depressions in a front face thereof and protruding ribs defining and bordering the depressions. The depressions are sized to receive respective artificial masonry units in a close-fitting relationship. The artificial masonry unit comprises a body bounded by a front face, a back face, and a lateral face providing a thickness to the unit, and a back peripheral edge joining the back face and the lateral face. A tooth projection is projecting from the lateral face next to and parallel to the back peripheral edge for thrusting into the protruding rib when the masonry unit is inserted in a respective depression. Thanks to the tooth projection that is thrusting into the rib of a respective depression and that helps retaining the masonry unit within the depression prior to mortaring the wall, there is no need for using a mixture of cement to temporarily retain the masonry units within the depression. A method and a kit for making a masonry wall with the above described masonry unit is also disclosed.