This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
To any future monthly posters of SQ threads, please remember to add the "stupid_questions" tag.
Err... I don't know. Proposing with a fake £10 ring sounds cheesy to me. You can always go shopping together for the wedding bands :-)
GIA and AGS certificates are both fine. EGS and IGL are more iffy in the sense that they will grade a diamond higher than GIA or AGS would -- downgrade their ratings one or two notches for comparison.
Well, the first choice is between yellow and white -- some people want yellow (gold) jewelry. In white, do NOT buy white gold, it's rhodium-coated and the coating wears off. You are supposed to renew it every few years. Buy either platinum (expensive) or palladium (less so).
A friend of mine proposed with an engraved multitool... that's a very special pair of people though.