Why are ASX 200 mining shares are smashing the benchmark on Wednesday?

Rio Tinto, BHP and Fortescue shares are all charging higher today. Why are ASX 200 mining shares are smashing the benchmark on Wednesday? You're reading a free article with opinions that may differ from The Motley Fool's Premium Investing Services. Become a Motley Fool member today to get instant access to our top analyst recommendations, in-depth research, investing resources , and more. Learn More S&P/ASX 200 Index (ASX: XJO) mining shares are racing ahead of the benchmark in early afternoon trade on Wednesday. Here’s how the big three mining stocks are tracking at the time of writing: Fortescue Metals Group…