Huw Eastwood wroteThat’s a lovely key, unusual
At Windsor Castle they have double ended keys (by Hobbs) which was effectively a master key system where the key instead if the lock was masterkeyed. Folding keys are generally either to stop them sticking out of the lock too far or to be convenient to put in a pocket - with a double ended key I would expect the latter.
i don’t know if any stylistic difference between crowns for George ⅘/whatever, but suspect that GR may not be George Rex - probably the initials of the key holder.
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