I think you might be a little confused. Why would anyone be wondering that?
Those old obsolete certificates are no longer related to the value of silver itself, and have value only as a collector's item. See en.wikipedia.org/wiki/Silver_certificate_(United_States)#End_of_the_silver_certificates
Gold & silver have retained purchasing power, versus the dollar & inflation, over the decades. Attached is a chart for gold. Silver would be similar.
"My favorite example: In 1964, a gallon of gas in the U.S. cost 25 cents. Quarters were still made of 90% silver in 1964. To buy one gallon of gas, you could pay with one silver quarter.
Today, the silver in that quarter is worth about $4, which is also what a gallon gas costs. The gas price rose 15 times since 1964, so the paper dollar purchasing power is less than 7% of 50 years ago. But the buying power of the silver is worth about the same after 50 years."
moneymetals.com/news/2014/08/14/reprogram-your-mind-gold-and-silver-dont-change-paper-money-does-000588