Silver serving spoon hallmark

I realise I have been using a very old spoon in my caravan for years and thought it about time to understand something about it.
Can you help with telling me about this spoon?
I have attached the hallmark photo.
The handle is engraved M~M B 1751


You may wish to bring the spoon in from the caravan and give it pride of place in a display cabinet. It is solid silver (sterling, 925 standard) and was assayed in London in 1757. The makers are John Kentesber & Thomas Grove who registered this mark in June 1757.

Thanks - intriguing!
Should it just be polished with silvo?
Is there any financial value in such items?

Silvo should be OK and there is definitely some value to the spoon. Condition is important so value for a table spoon (8" long or so, which I assume is the size of your spoon) could be anything from scrap value up to £40-£50.

Thanks for your comments. It’s 8 and a quarter inches long.