This is one of about 100 pieces made of the proof halfcrown of 1746. It was originally one of a 4 piece set, sixpence to crown. Of the 100 pieces, many have been impaired over the last 271 years. This one has not.

I have a matching shilling as well but not the sixpence. the crown in this condition Im afraid is too expensive for me so I would be content to get an original unimpaired sixpence. Although special proof strikes were made earlier, this 4 piece set is reputed to be the earliest proof set for collectors produced anywhere in the world.