Geological investigations into silica deposits around New Zealand hold the prospect for a renewal of a local sand mining and processing industry for glass manufacture. The NZIMMR is looking to work with sand producers to create a high-value, New Zealand supply chain.
At one-time silica sand was mined in Northland, and supplied to glassworks in Auckland. That silica requirement is now imported from Perth, Western Australia, at 60,000 tonnes a year. Ordinarily, silica is a low-value, bulky product where the economy relies on proximity to markets. NZIMMR’s silica sand project is aimed at adding value to New Zealand’s silica sand resources.
Led by Chief Technical Officer Kirsty Hollis, silica sand is an emerging project for NZIMMR, with a view on improving the price point for mined and processed silica sand in New Zealand. Prices globally vary from $50 per tonne to $5,000/t, depending on product quality and applications. The starting point for New Zealand resources is more likely to be in the realm of $100-150/t. This compares with $10-20/t for sand supplied into local asphalt or concrete industries, so a significant value-add.
As well, sourcing silica from New Zealand instead of Australia would reduce the carbon miles of transport, and create New Zealand jobs.
NZIMMR’s initial industry review has revealed several promising silica sand deposits in the North Island and the South Island, with further investigations underway.