Canadian firm strikes gold in first NZ drill hole

A Canadian company which has spent millions prospecting in New Zealand says it has struck gold between Rotorua and Taupo, though levels in the initial hole were not sufficient for economic mining.

Glass Earth Ltd - named for its use of hi-tech aerial surveys to "see" into underlying soil and rock - is exploring over 33,175 sq km in North and South Islands.

It said core samples analysed in Wellington from its first 360 metre-deep drill hole near Atiamuri, 25km southeast of Tokoroa, indicated it had hit a epithermal gold system.

Epithermal gold is usually deposited by hydrothermal fluids cooler than 200degC and less than 1km under the surface.

The first drill hole testing at the site "provides confirmation of the geophysical model used by Glass Earth in its search for buried gold deposits", the company told the Toronto Stock Exchange last night.

The site was worthy of further investigation, it said.

Planning of further drilling and resistivity work would be done while a second "target" 2km away.

Another 104 targets were identified by the aerial mapping, with a total of 21 listed as the most promising.

Some of those between Rotorua and Taupo have geological characteristics similar to those at Martha Hill, a Coromandel mine which has produced about 10 million ounces of gold in the past 100 years.

Four more likely drill sites are near the highway linking Rotorua and Taupo -- three are near Waihi and Martha Hill, and one is west of Te Puke in the Bay of Plenty, in a previously-mined gold vein known as Muir's Reef.

They were pinpointed by small aircraft that flew nearly 50,000km back and forth across the central North Island last year.

Searching for gold in the region has until now been limited by the 200m thick layer of volcanic ash that blankets the underlying rock.

The aerial mapping was followed by ground testing and soil geochemical sampling of soils.

Glass Earth's exploration work is headed by its chief operating officer, New Zealander Simon Henderson, who 26 years ago was a geologist at the Martha Hill mine and later at the nearby Favona prospect.

Glass Earth acquired six exploration permit applications in December 2005.

In the South Island, the company's exploration efforts have been focused on the Otago Region for mesothermal gold targets laid down by hydrothermal fluids at higher temperatures, between 200degC and 300degC.

- NZPA