"For the first time ever, we've got 190 countries agreeing to sound the death knell for coal power," he said.
"We've kept 1.5 alive and made huge progress on coal, cars, cash and trees.
"And while there is still so much that needs to be done to save our planet, we'll look back at COP26 as the moment humanity finally got real about climate change."
Negotiators ended two weeks of intense talks on Saturday, with countries agreeing the Glasgow Climate Pact to limit global warming to 1.5C and to "phase down" - not phase out - unabated coal power, following objections led by India and supported by China.
Pressure on big miners to quit the coal business has done nothing to reduce supply of the controversial fuel and might even be encouraging production, Mining Journal columnist Tim Treadgold wrote on Friday.
Some countries did commit to phase out coal and to end international coal financing, the UN noted.
"We can now say with credibility that we have kept 1.5 degrees alive," COP26 President Alok Sharma said.
"But, its pulse is weak and it will only survive if we keep our promises and translate commitments into rapid action."
The International Council on Mining and Metals president and CEO Rohitesh Dhawan spoke at a climate governance initiative event at COP26 and said society wouldn't fully realise the energy transition without close collaboration across value chains.
"Our members recognise the need for an urgent global response to the threat of climate change - across all areas of society and the economy - and are committed to being a part of the solution," the council said.
Its members last month pledged net zero on scope one and two emissions by 2050.