Offshore ironsands explorer TransTasman Resources says it has confirmed "inferred" and "indicated" resources of around 200 million tonnes to the internationally recognised JORC code standard in its southern Taranaki exploration zone.
The company announced a resource of at least 102 million tonnes earlier this year in the zone off the coast of Patea, within the New Zealand 12 mile nautical limit, and has since been granted further exploration rights in an adjoining 3,134 square kilometre licence in the Exclusive Economic Zone.
The find doubles the size of the potential resource so far discovered, although the JORC code "inferred" and "indicated" standards are still short of a proven resource.
The latest JORC-compliant estimate is based on ironsands yielding titano-magnetite iron ore at a 60 per cent concentration. Some 70 million tonnes is at the "inferred" level, and a further 130 million tonnes is "indicated".
Chairman Bill Berend says further exploration is expected to "increase very substantially" the size of the mineral resource so far uncovered.