This is a long shot, but, does anyone recognise the very worn armorial on this set of three early 18th century knives?:
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I appreciate the engraving is hard to make out, but it is made up of a circular device with six pellets, containing a double-headed spread eagle and surmounted by a left facing demi-lion rampant.
The knives are likely early 18th century, due to the lack of a 'hump' on the scimitar blades.
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The hilts are unmarked, but the blades are likely London-made as the 'dagger' mark is just visible.
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As said, a long shot, but any thoughts appreciated.
Trev.