Edinburgh maker?

I have a pair of Celtic Point egg spoons with the town mark for Edinburgh, the tricuspid George III duty mark for 1797-8 and an unfamiliar maker’s mark of G&M (the ampersand is of the Saxon variety and not the more common Roman type).

Jackson’s doesn’t offer any clues. I believe there have been recent developments in ascribing Scottish marks and there are several books now with more recent and up to date information. Unfortunately I do not posses these books, but perhaps someone here does. Can anyone shed any light on the makers of these spoons please?
Edinburgh_eggspoons_c1797_08.jpg

For one possible option on the makers, I would suggest Graham and McLean of Glasgow (listed in the index of Glasgow makers in Pickford’s Jackson). Their partnership mark was almost assuredly a “G and M” of some form.

That style of ampersand was used earlier by Alexander Aitchison (1) and his son Alexander in Edinburgh in the early 1770s.

Hope this is somewhat useful.

Regards,
Rod

Thank you Rod for the reply. I also saw Graham and McLean under the Glasgow goldsmiths, but dismissed it as their earliest recorded mark is of 1801 and I was ardently hunting for a maker of 1797 or earlier. However, I have since read that Edinburgh carried on using the tricuspid duty mark for some years after 1797 even though it was introduced solely for the 1797-98 year.