A couple of images of Black Lion Yard, a narrow lane linking Whitechapel Road with Old Montague Street, in the east-end of London:
Since the 1920's, Black Lion Yard was famous for its jewellers' shops and was known as the 'Hatton Garden of the East End'.
Both images, the first from 1926, and the second from 1961, show the premises of Joseph Leton. Joseph established his business at 7, Black Lion Yard and continued there until the demolition of the area in 1972 to 1975.
Joseph Leton was noted as entering his mark with the Glasgow Assay Office. Joseph Leton was formerly known as Joseph Letowsky, and under that name he entered his mark, 'J·L', with the London Assay Office in 1902. He was born in Russia and naturalised on the 17th July 1906.
Trev.