Rolex Day-Date 18238 Onyx Dial T Swiss TOne of the coolest things about collecting Day Dates, is the huge variety of dials that were made for the watches over the years. Few are more desirable than the ones made from hardstone and one of our favourites is the onyx dial. Deep and rich black, the stone gives the watch a unique look and we have a very special one correctly signed T SWISS T. An important note is that in most cases you will see these watches fitted with the service dials signed