Thanks for all your help on this one.
I've gone for GAVID/GAVED.
My reasoning:
- there are only 3 Elizabeth COADs in the whole of St Mewan's PBR, only one suitable (1866, age 71) but no matching John;
- the "John" surname certainly looks more like GAVED/GAVID;
- the age range of surrounding GAVED stones (1770s-1840s) in a graveyard where most early stones are beside the church;
- the physical setting: it's like a clearing in a forest (yeah, I know, romantic imagination getting the better of me!) although the trees must have come later. But it's as though the children (and at least one granddaughter) started dying, were buried near each other, and JOHN & ELIZABETH put a tomb in the middle ready for themselves.
- the GAVED name is prominent in this churchyard (although no-one knows the name today) and there appears to be a London connection somewhere, so "moneyed" appears to apply. i.e. able to afford a large plot?
I don't like putting guesswork online, but there doesn't appear to be any definite information. It's this or nothing.
At least this way any future researchers know that the grave exists and can come and pull my theory to pieces!
Jane