Wedding and engagement rings are all about symbolism
That's the point of them. So I think the ring's provenance is important.

They're supposed to symbolise your happy relationship, so a brand new ring or a ring from a much-loved relative who was happy in their marriage is good.

A second-hand ring from an unhappy stranger is bad.

Just because it destroys the symbolism, not because it's bad luck.
( in vino veritas, Fri 10 Jul 2009, 10:27, archived)

What about a second-hand ring from a happy stranger?
Or a second-hand ring from someone who's unhappy but you know quite well?
( Theoban What of it, Fri 10 Jul 2009, 10:29, archived)

Neither of these are appropriate
due to either unhappiness or distance of relationship with previous ring-owner.

It seems unlikely that a ring with such a history would adequately symbolise the new marriage.
( in vino veritas, Fri 10 Jul 2009, 10:34, archived)