This "crown handle" porringer is of a type that is related to the "initial" handled porringers. Dating from the last quarter of the 18th through the first 20 years of the 19th century.
This handle is very similar in design to the large "SG" handle but there are differences.
Measuring 5 7/16" in diameter. The metal is in fine condition. The linen mark is faint due to the fact that the handle mold was not tight against the body of the porringer when the metal was poured. In the photo of the back of the handle there is distinct "flashing" where the metal oozed beyond the constraints of the mold.