Is this a Sheffield Sterling Mark? Whos is the Maker?

I have had no luck identifying this Sterling Spoon. Have sent it to various"experts" but they cannot identify it. It says Sterling on the handle and has a lion (left), R (center), and crown (right).

It is an absolutely beautiful spoon.

The limitations on photo size here do not do it justice.

I do know the age is is pre 1900.

Could anyone help me identify this?

Thank you for your thoughts.
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Not Sheffield; a Sheffield mark would not normally be accompanied by “sterling”. It’s almost certainly an American manufacturer, but not one whose mark I recognise.

Thank you for your reply. Here is a better photo. I agree it is likely an American made spoon. Perhaps someone will view this and have some additional thoughts.

Best regards,

Gregg
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