Help with JM Hallmark

Hi,

Can anybody please help identifty this for me?

I assume from parts of the stamp that its from England due to the Lion and is from London post 1822 as the Leopard seems to have no crown?

I’m unsure as to what the i stands for, and also unsure as to what the J.M stands for, who it is and what period.

I can find other J.M but not in this font or with this diamond shaped background.

Any help appreciated.

Thanks

This is a London 1924 hallmark. The maker’s mark is JH, which is the mark of J Howell & Co, cane & stick manufacturers of Old Street, London. JH is the initials of the company’s principal, Jonathan Howell.