VERY RARE Rolex ref. 6599 Oyster Perpetual solid 18k gold mens watch. Incredibly rare model.I suspect the watch is all original with exception to the crystal, gaskets, strap, and buckle. I have just acquired this fine timepiece and have done nothing to it aside from replace the strap and buckle, remove the caseback for photos of movement, and clean it a bit with a couple q-tips to remove some debris in crevices.Case size is 36 mm. The strap is a generic leather strap, and the buckle is an gold plated Rolex buckle which I had in my inventory. The holes in the strap are a bit smaller and the tang of the buckle is a bit larger a bit tight pushing through.I had the watch running for about 12 hours and observed that it ran about 5 seconds fast over 12 hours. I also put it on my timegrapher and it showed +6 sec per day. So, it running quite accurately without any adjustment made, at the time of this listing.The serial number is 4238XX (last 2 digits not disclosed for security reasons...some buyers do not like the serial number of their newly purchase Rolex to be publicized). This dates the watch to 1959.Movement is Cal. 1030 with butterfly rotor. Working as it should, rotor is rotating and winding as it should.Some blemishes, like spots on the dial, perhaps a couple pieces of debris under crystal. Its pretty clean already and I do not wish to take it apart. The rotor also has some spotting. I do not know any service history as I just acquired the watch.I have only sold a few watches that qualified for ebays authenticity guarantee process, and I am not sure if the authentication will be added to this listing until after I list it. If you see the authenticity guarantee on the listing, this means that it will likely go to a third party authenticator before being delivered to you. I have had this happen a couple times, and it delays delivery to you by only a couple days, if it happens.