Kakula's 4.41% Cu at 2% cutoff puts it in the top 5 underground mines worldwide (by grade). Some will argue that 4% is moderate grade, but there are only 3 mines that currently have better grades. Check out the following link.
https://avancoresources.com/wp-content/uploads/PressClippingMiningDotComTheWorldsTop10HighestGradeCopperMines20Feb17.pdf