Ann: Maroochydore Cu Co Project Initial RC Drilling Results, page-4

Copy and paste from a previous poster.

Globally, the average grade of copper ore mined has declined by 1.8% per year over the past 12 years to 0.59% in 2017.

Interestingly Cobre Panama is mining 0.4% Cu. In 2017, Sulphides accounted for 62% of total ore. The average mined grade fell from 0.77% (2005) to 0.58 (2017). Oxides averaged 0.47% in 2017, virtually unchanged from 2005.

Escondida in Chile has 11.5 billion tonnes of resources at a grade of 0.59% copper, with reserve of 5 billion tonnes at a grade of 0.71% copper.

Freeport uses milling, crushed and agitation leaching at its open cut project in America. The lower cut-off for milling is 0.18%, crushed leach 0.12%, ROM leach 0.05%.