1926 Portoro Marble ATO clock Leon Hatot.

I recently purchased this beautiful ATO clock from a vendor in Canada. I loved the yellow, white, and grey marbling effect on it. The dial in rough shape. It has the logo of the store or jewelry store that sold it on the dial "Mario Y Diego". The back features a regulator with address was "23 rue da la Michodiere, Paris". so along with John Lock's criteria (face and hand design) for this clock the date of 1926 is correct. This clock has kept perfect time since I unpacked it. I don't know what it is about the Portoro Marble that makes it so heavy, but it is heavier, I guess it has a higher iron content than other marbles. Although it was made prior to 1929, it is listed in Hatot's 1929 catalog.