I'm just googling, but FWIW, from 2017: The China Carbon Market Just Launched, And It's The World's Largest. Here's How It Can Succeed. https://www.forbes.com/sites/energyinnovation/2017/12/19/the...

At a cursory glance, it seems like it's still ongoing, at a price of 8$/ton: https://www.icf.com/insights/public-policy/china-carbon-pric...