Congratulations!!! She said yes. Now its time to choose a wedding band. A friend of mine is in that very situation and has been overwhelmed by all the choices; choices that he didn't even know exist, mainly what metal to choose.
There are several different kinds of metals used to make wedding bands. There's gold, platinum, rhodium, titanium, silver, tungsten carbide and last but not least, stainless steel.
Gold
What is it about gold that makes it so popular? Is it the bright yellow coloring or all the history it has as many of the early American settlers gave their all to find just one nugget.
When shopping for gold consider the karat and the color. Karat is the measure of actual gold in the metal. Most people don't realize it but you will never get a piece of jewelry that is 100% gold.
FYI:
9kt gold contains 37.5% pure gold (375 parts per thousand parts).
14kt gold contains 58.5% pre gold (585 parts per thousand parts).
18kt gold contains 75% pure gold (750 parts per thousand parts).
When it comes to colors, there's yellow, white and rose. Yellow gold is made by mixing pure gold with alloy metals such as copper and zinc. Rose gold is made using a mix of pure gold with alloys including copper. The copper provides the rose-reddish color. White gold is an alloy of gold and some white metals such as silver, nickel and palladium.
Platinum
Made popular in the late 1990's and early 2000's by trendsetter Jay-Z, platinum is slowly but surely become the first pick for many choosing the metal of their wedding bands. Platinum is a white metal that is almost its pure form (95% pure). It is dense and heavier than gold. It is also more expensive boasting twice the price of 18kt gold.
Silver
Silver is a white-grey colored metal which is less expensive and softer than gold, platinum and titanium. 
Unfortunately, silver is not suitable for ladies engagement rings as oxidization causes the silver to turn black. Using silver jewelry cleaner you can get your ring back to normal but who wants to do that?
Tungsten carbide
Known as tungsten, this metal is a very hard, strong and heavy. Highly scratch resistant, Tungsten may be the perfect ring for your rough and tough future husband as they do not scratch with everyday wear like gold and platinum does. Remaining bright and shiny, it doesn't need the polishing maintenance that gold, platinum and titanium do
Stainless steel
Stainless steel is a metal not traditionally used in fine jewelry but some people wear it. Stainless steel is a relatively hard and durable metal. It is particularly popular in men's bracelets, necklaces and men's dress rings.
Whatever metal you choose makes sure your wife-to-be makes the decision as the wedding is her day!
1. I dont realy care if its Platinum or white gold!
As long as the VS bling, look at the light show!
- 50 Cent in song Stunt 101
Big Mitch at 12:46PM on Jun 19th 2008