Victorian Scene Fashion Necklace

Found in a box of items purchased at an estate auction. Chain is 20" L. The pendant is 1.5"L x 1.25" W. The watch on the back of the pendant has "Dorset" at the top of the watch face and "Swiss Made" at the bottom of the watch face. At the bottom of the pendant there is a mark of "M", a pick axe" and another "M". Can anyone identify this piece for me. Thanks so much.