In 2018 I mentioned : The life path of a mine
Discover a deposit, bring value, get the authorizations (permit), build it (financing) and put into production cannot be done as fast as some people love to think.
Hereafter some graphs showing the required duration for all steps to enter into production.
Ascertainment : It needs (average) 16,9 years. Some countries are showing a big spread between the shorter and the longer period. I assume it is because of the difficulties to get a permit (The Grail) and financing problems (difficult market, hard to raise money).