I proposed to my wife off the cuff when I was pissed and so was she. Three months later she chose her own ring- a cubic zirconia from Ernest Jones. Cost me £110. When it's clean it looks superficially like yours- at least to people like us who don't have the first idea about how a diamond is supposed to look.
I'm sorry, but I just can't get excited in any way about diamonds. So they sparkle a bit. Big w00t.
Fair play to you mate, you're clearly a capable and successful guy, and you seem to genuinely care for your wife rather than marrying a trophy bit of fluff, so.... If I was in the same position my wife would prefer a couple more holidays a year, is all.
Good thing you didn't then- secondhand diamonds are pretty worthless.
Albeit this article os from the last recession:
http://www.independent.co.uk/news/wo...g-1557274.html
Here's something a bit more recent:
http://www.straightdope.com/columns/...e-of-its-value