The Parker 61 Custom Insignia, also known as the 'Signet', was introduced in the U.S.A. in 1958 and a few years later in the U.K. This pencil was made in England and probably dates to the 1960s.
The cap carries a shield stamp which reads 'P., 1/10, 12 Ct., RG' indicating that the pencil is one tenth by weight 12 Carat Gold. It is also stamped 'Parker, Made in England', along with the Parker 'halo' logo.