Mortar between fire brick on oven floor

[Susan Egglaine]

Hi all! New here. My mason used mortar between the fire brick on the oven floor.This is only the second oven he has built. He is very good and pleased with how the oven looks. I did a cross between the Naples and Tuscan oven style. Is this going to cause problems? Anyone else have an oven floor like this? Anything I should ask him to do? He still has to put on the outside stone which came Friday, so I have not started the curing process yet.
Tries to upload a pic but failed. Thanks for any help!