Footed shallow dish/tile, marked with the letter "f" and the shell symbol

Good day to everyone.

I have a small footed square shallow dish/tile. The marking is stamped with incised letter "f" and a symbol looks like a shell.
Color of the clay is dark pale grey, and partly unglazed. The glazes are forming the drips over the grey clay and colors of the glaze: off-white color and dark teal-blue color. The glaze placed diagonally. Similar glaze design on the base of this footed shallow dish/tile.

Measurements: 5 1/4" x 5 1/4", height 1" - 1 1/2"(on the corners)



Maybe anybody knows or came across this marking, or maybe saw something similar in designs? Possible origin, circa, artist?

Any suggestion and opinions I will appreciate greatly.

Thank you in advance.