I've found this fact while I was trying to look for answers about this question.
"No doubt, in the natural, what they are saying has some validity, that silver will outperform gold in the long run. And when the dollar finally collapses and becomes worthless, silver and gold values will find their final resting places dictated by world-wide supply and demand. For example, using the arbitrary numbers of $10 per ounce for silver and $600 an ounce for gold, silver could easily reach $110 per ounce ($10 per ounce times 11 = $110) and gold could easily reach $3,000 ($600 per ounce times 5 = $3,000)."