There are multiple regrind mills in the circuit at renison,...

There are multiple regrind mills in the circuit at renison, falcon high G separators and tin flotation. I'd say there's a lot of money been spent on getting the plant right. Masterful metallurgy by MLX and gritty determination has made the operation work. As for history -rip out the high grade and don't worry about how much ends up in the tailings. These days operations, particularly at less than 1% tin are very sensitive to plant performance given the ridiculous operating costs of the western world and masses of CAPEX to cover.