Hi Patsy
[Drat ... having some trouble at the mo, getting my "posts" to post. GRRR !
Just lost a whole lot of info so will have to try it again. ]
Yep, it is indeed "Sandiacre" - Derbyshire.
And I'd earlier found a census return 1841 for William MASON - mechanic, wife Lucy (Lucy Ann), daughter Lucy, (Lucy Ann) aged 15 / son William (13) ... and John MASON aged 10 years (presumably another son ?) ... and born c. 1831 !!
Resident at Sandiacre, Derbyshire.
[Might have to "eat my hat" re: the earlier Derbyshire marriage of a John and Mary Ann - 1851 ... although it is the only MASON / MARSHALL marriage which stacks up.]
~ Lu