The 'Aerometric filling' Parker 51, this pen, was introduced in 1948 and went on to become the most successful fountain pen of all time. Date coding on English pens ended around 1955 and a 'halo' was added to the cap in 1957/58, the pen has no halo or date code so 1956 is a good date estimate.
The pen has been fully serviced and tested. Servicing is particularly important if a 51 has been unused for some time as the fine fins in the ink governor, under the hood, can become blocked.
The 14 Ct. Gold nib is concealed by the 'hood', this keeps it moist and offers some protection. 51 nibs were largely hand made, including cutting the slit, so there is some variation between individual nibs. This one writes with a medium line, perhaps a little on the fine side.
The pen is in excellent condition. the pen body has a showroom finish and the 'Lustrslloy' cap is free of dings. The chrome plated 'arrow' clip is secured by a brass stud capped with a pearl coloured end 'jewel'. The Teal colour, named after the wing flash on the duck with that name, is most attractive, it is definitely Blue but has a distinct Green tinge.