GNS Science conducted a review of Northland’s potential exploitable mineral resource base in 2007.   In this report the authors concluded that the value of Northland’s annual mineral production could increase from the then current level of $58m to $354m within a fifteen year time frame.  This would entail:

• An increase in production of aggregate and limestone to past maximum annual levels,
• Development of a gold-silver mine,
• Development of a second metaliferous mine (eg aluminium, copper or gold-silver)
• Development of a second halloysite clay mine
• Reintroduction of silica sand mining,
• Small mining operations in one or more commodities such as bentonite, coal, feldspar, kaolinite clay, kauri gum, peat, and zeolite.


The GNS assessment has been used for modelling an expansion of mining activity in Northland.  It presumes that Northland’s annual mineral production will have increased by 610% by 2030 (ie 354/58), but that no production growth will occur prior to 2014.  Implicitly it assumes that the ratio of value added to gross output remains constant.  Output from the mining industry declined on average by 0.3% per year in the ten years to 2008.  The baseline forecast is for further declines in mining output to average 1.0% per year in the 22 years to 2030.  The accelerated growth scenario would instead see mining industry output increase on average by 7.1% per year.