For all those looking for platinum jewellery out in Dubai my fiance bought my engagement ring at Gianni Martinelli's at the Gold and Diamond Park (although I think they have shops in a few places). Just had it valued today at £5,000 and we only paid £1,500.
The Gold & Diamond Park IMO is a lot nicer than the souk although it is much smaller. We also looked in the Madinat Souk which is lovely and worth a visit.
I spent some time on the site looking at where we could buy before we went so thought I'd offer this up. I was a bit worried that I would have to settle for white gold but there is plenty of platinum jewellery to be had.