hi hope someone can help i found a chanel j12 with dimonds round the edge washed up on the river in london how can i tell if it is real and if there is any markings on it or anything on it that should point to a fake the watch has been in river so is in poor condition but has loads of dimonds around the edge any help with this please and if it was real how much would the dimonds be worth . ps it is a black watch thanks