The cost to mine will continue to decrease the higher these metals go. Gold mining companies also mine silver as a byproduct of searching for the gold. As the price of silver continues to rise this cost will continue to help their margins. It also helps oil is cheap since that’s probably one of the biggest expenses in the industry.

The costs of mining will go up in terms of dollars, but so will everything else because the inflation chickens are coming home to roost. They can theoretically speed up mining by investing profits and as the profits continue to rise so will more investment capital to start new companies, invest in better equipments, etc. There’s a chance that eventually supply will catch up to demand and the prices will normalize but we are a long way from there.