A William Ivin married Mary Cooper, St Giles Cripplegate in 1774.
20 November 1775
Entered a mark as bucklemaker at 10, Norman Street, St Lukes
1775
Christening of Mary daughter of William, Silversmith & Mary Iven, (no address) at St Luke, Finsbury .
1776
Burial at St Luke, Finsbury of William child of William Iven [sic] , died of convulsions, (no address.)
1777 .
Burial at St Luke, Finsbury of child Mary Ivin, who died of smallpox; no parents or address given
1777
Christening of William son of William & Mary Ivin , no address given at at St Luke, Finsbury .
From the silversmith reference at St Lukes in 1775 it seems very likely that this is the correct family.
There was also a christening of Mary daughter of Benjamin Copper [sic] at St Matthew Bethnal Green in 1750.
The entry shows no mother's name nor address and carries a note "15 years" which suggests she might have been born in 1739. If this is the Mary Cooper who married Ivin then she would have been c 39 years old in 1774 when the marriage took place. Very speculatively Mary could be related to Benjamin Cooper, a long lived sliver bucklemaker see viewtopic.php?f=74&t=26754