Patek Philippe 18k ClamWin Shell w Tiny Porthole Circa 1800s Metalic Blue Hands

Rare 81Grams 18KT 48mm Patek Philippe! This was my Grandfather's watch given to him by his father, my great grandpa. My grandpa was born in 1898 in Europe and left this to me and I've had in safe box all these years Beautifully crafted 18kt gorgeous dark deep rich Gold color with the deep teeth on crown sharp and not worn much at all. See photos and I'll attempt to answer best I am able. I took to the Jewelers across the Bellevue Square mall on the 1st floor of the Daniel's Broiler Building and they told me it is circa mid to late 1800s. It quite unique and it's time to help my twins further their educations now in grad school. Many thanks for your consideration. Sincerely.