Historically, also, the gold/silver ratio is about 15 to one. So even if gold just stays where it is, that would mean 40 dollar silver.
If gold were to go to the inflation adjusted numbers, that means silver in the 120-140 range.
But it's just numbers. It may be that by the time that happens, TP is worth even more!
I don't have the charts at my fingertips, but I'm sure someone does. Over the last 10 years, until very recently, gold was $200-400/oz, and I think silver was $2-5. The old, "fixed" price, from 1933-c.1975 was $35 for gold and $1.29 for silver, or about 30-1.
It is true that at the top of the speculative bubble in 1979-80, Gold was 850 and silver almost 50, or close to 16-1, but Silver ws much more "bubbled", and fell much faster, so the ratio grew back towards 30-1 or so.
I'm not saying that there is any "right" ratio (in fact, I would say that there isn't), but I think that the times when a free market price of silver was as much as 1/16 that of gold have been pretty rare -- but I'm sure someone has the charts with real answer.