1970 Rolex 1600 Sigma "Pie Pan" Dial Datejust timestamp: https://imgur.com/a/k4Euv5H Into the late 70s, Rolex stamped the Greek letter Sigma (σ) at six to denote use of gold, while "Pie Pan" refers to the outbound minute track's soft chamfers (slope descending into the watch's rehaut). Both of these details were phased out with the release of the 1600's successor. Another charming inclusion into Rolex's strange and intricate chronohistory. Case: 36mm Stainless Steel, Bezel: Smooth, Dial: Sigma "Pie Pan" Brushed Creamy-Silver, Bracelet: 62510H S-stamped Oyster, Movement: Automatic Rolex cal. 1570 4,200USD Shipping included; Venmo, Zelle, Paypal, and wire all accepted forms of payment. Connect with me [email protected] for any questions about this 1970 Rolex 1600 or any of our other offerings.