1841 UK Census for Thorn Cottage, Holloway shown as of independent means aged 70 years.
England & Wales Deaths Index for Islington register dated 1st quarter 1848.
For further detail of the Lias business see John Culme's Directory of Gold & Silversmiths 1838-1914 Vol. I p.295-6.
The Will of John Lias, silversmith late of Finsbury Street, was proved for probate on 22nd March 1848 (National Archives reference PROB 11/2071/289).