TBVECHI Concrete Cement Wall Floor Mat Polyurethane Mold Vertical Stamp Mat 15.7"x7.8" x 0.6" 1.5 kg (15.7"x7.8" x 0.6")

I had to return this but it looked like it was gonna work. We went a different route thats why i returned it

Use a thick, stiff mortar and when it has set to the point that it will take a 1/2” deep thumbprint, you can press this mold into the mortar (press hard, it takes some strength), and create a realistic ledger stone. Use vegetable oil on the form as a mold release, and peel away from one side to allow the concrete to release without sticking to the form from suction.