What's the Deal with Gold Coins?

Hey there.  Am I the only one that wonders why we see ads on TV selling gold coins for less than the market value?  I was up late last night watching TV when I saw an advertisement that claimed that the coins were worth hundreds but they're selling them for $20.  It got me wondering if the price of gold is wildly fluctuating that one day, an ounce is worth $20 and the next day, it's a few hundred.

That got me wondering if it's a good investment to keep track of gold prices.  It seems like a good idea.  Invest some money in a commodity that is in demand.  You see gold everywhere.  Watches, necklaces, teeth... Donald Trump's place.  lol  I mean, if gold is that valuable, I don't see where you can go wrong in investing in it.  But then again, it is investing and there's always that risk of it's value decreasing.  Maybe if I go to a gold spot, where they buy and sell gold, to see what's up.  If they say that it's profitable, it may something to consider.  If they say they're barely breaking even... then it's something to think hard before doing.

I'm wondering if any of you have had any experience with the gold trade.  I know that now there's a service where you mail your gold scraps and you get cash for it.  Is that any good?  Would you rather just go into a shop and see what you can get?  I'm curious, friends.  Let me know.  Later!