These are two examples of Grandfather Clock Dials, these are the early brass type as you can see the 1st picture is a dial which needs silvering, and the second has been restored & silvered, silvering is a chemical process using silver oxide which causes a chemical reaction with brass, this process dates back possible to the middle of the 17th century, both of these clock dials are c1750.
Brass dials on Grandfather clocks were the most common dials up to around 1800 then it started to move more to the painted dial style of dial, the dials often depicting flowers and, on some of the very large ornate type, depicting stories often religious or a local battle or folk tale.