Postby silvermakersmarks » Wed Jan 06, 2016 6:54 pm
This mark is not shown in the Registered Marks section of Grimwade's book of London goldsmiths' marks. There are 2 missing registers of marks, the 1738-1758 Smallworkers Register and the 1758-1773 Largeworkers Register; it is most likely that this S·J mark would have been identified in one of those. However Grimwade does note a similar mark seen on some "fancy-back teaspoons" from c1775 with the attribution "Samuel Jerman?". Your hallmark bears the "L" date letter for 1766 so may be by the same maker.
Phil