Combined geological, aggregate mining data, and verifiable historical record show that about 190,000 metric tonnes of gold and some 1.6 million tonnes of silver have been mined physically throughout history.

Now, that's ~8.4:1 average, total...in 2016 it was 8.5:1, and apart from a couple of peaks in 1835, 1890 and 1920 (all much lower than the current ~65:1 ratio "price") it's been around the 8:1 ratio for nearly 200 years
it's real value? 
https://sdbullion.com/blog/how-much-silver-gold-is-there

Now, that's ~8.4:1 average, total...in 2016 it was 8.5:1, and apart from a couple of peaks in 1835, 1890 and 1920 (all much lower than the current ~65:1 ratio "price") it's been around the 8:1 ratio for nearly 200 years
https://sdbullion.com/blog/how-much-silver-gold-is-there
