would like a quite chunky ring

Hi Guys, I was just wondering what you guys think about this ring? http://www.allthatsparklesdiamonds.com/381ctw-diamonds-and-blue-topaz-trillion-cut-r382.html

I'm looking for a blue topaz ring to wear as an engagement ring. I already have a ring, but I'd like something a little more non-traditional that I can wear when I feel like a change. I've checked the jewelers and I didn't like anything they had, so I checked online. I like this one (http://www.ice.com/customer/product_detail.jsp?product=51236243&sourceID=googla_42&srccode=cii_14110944&cpncode=09-24917000-2) but I can't figure out how big the stone would be. It says 4mm width and 6mm height. Does anyone know how big this would be? I want something that's not too big and not too small: maybe something that would be the equivalent of a 1 carat in diamonds. If I had a ruler in my house, I would have looked instead of asking. I also found this one: http://www.overstock.com/cgi-bin/d2.cgi?PAGE=PRODUCT&PROD_ID=1786205&cid=97273&fp=F. Which do you prefer? My fiancee totally supports my decision since 1.) I picked out the first one as well. 2.) I paid for half of my engagement ring and will be paying for half of this one.

how much is a 1 karat Topaz ring that is clear and has an oval cut in a white 24 karat band?