Buenavista Zinc is a small zinc-copper deposit inside the big Buenavista copper open pit mine. In 2018 Grupo Mexico was expecting to exploit this also as an open pit mine producing 80kt/a of zinc and 20kt/a of copper in a 15kt/d concentrator. However, during our 2019 research visit we found out that the new plan was to have a 20kt/d concentrator. This change was included in our current (2021) analysis. Grupo Mexico estimates production startup for 2023. Previously we had this for 2021. Wood Mackenzie’s asset reports are built from the bottom up, incorporating a number of granular data metrics to ultimately produce our industry standard cash operating costs.