I've never traded them, so I'm unsure how precise the mathematics/correlation is to actual gold, so do some research before getting into either. As w/ most leveraged ETFs though, there is seemingly more risk to the downside.
No clue about CDE
Found these on the web too, but unsure if leveraged:
I would stay away from mining stocks...especially tiny cap ones. I personally view these trades as gambling. Even if gold/silver prices go up, these companies need to have and/or find gold/silver to make a profit.