Anyone know this assay office ? building with roof & col

[redpoppy]

Hi

Please could anyone please advise me of a gold assay office and country of origin for a gold assay office which looks a bit like a building or house with a triangle roof and columns in front.

It is on a gold brooch designed like a leaf, with the makers mark? H & I ? Have you heard of this maker ? It is marked 375 and the date letter 'r' any idea which year this is please?

Also is etched by hand '6/2139 g-g' this could be an auctioneers mark?

ANY HELP IDENTIFYING the assay office / country of origin / makers mark and year MUCH APPRECIATED THANK YOU!!!

The marks are too small to photograph sorry and barely visible under magnification.
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