And you could consider Moissanite for the wifes stones instead of diamonds.
If you get real moissanite then it is way rarer than diamond, but it is normally a synthetic form.
Jewellers have trouble identifying it from diamond and have to send it off to the lab.
I think it has a higher refractive index than diamond so will ‘shine’ more.
Plus you are guaranteed that no-one has smuggled it out in their teeth or that it hasn’t been used to buy weapons.
Some people have insisted on it for ethical reasons.
I mention it as I personally would prefer to spend more on the craftmenship of the ring maker than for overpriced bits of compressed carbon.
http://www.moissanite.net/diamond-substitutes.html
http://en.wikipedia.org/wiki/Moissanite