Alexander Mine, Reefton, Buller District, West Coast Region, New Zealandi

Regional Level Types
Alexander Mine	Mine
Reefton	Town
Buller District	District
West Coast Region	Region
New Zealand	Country

The Alexander gold mine is the southern most in the Reefton district, at 10 kilometres south-east of the Blackwater Mine. It has the eighth highest output for the district, at 48,492 tonnes of quartz crushed, achieving 41,089 ounces of gold, at a grade of 26.4. It was also the last gold area to be discovered in the district.

Gold bearing quartz float was discovered at the site in 1920, and mining ceased in 1943 due to a shortage of labour during World War Two. The lodes at the mine are named McKay, Loftus, and Mullocky, with a shallow dip. Gold is found locked in sulphides, mainly arsenopyrite, in a halo around the earlier mined reefs.

The site is not part of any walk trail, or tourist location, and has been covered by active exploration leases in recent decades. Access in theory can be obtained via the Snowy Road (difficult, and 4 wheel drive), which will get you within 2 kilometres of the mine, where the track crosses the Alexander River. It would appear not a lot remains at the site. The Edwards roaster, is a low rectangle of bricks, the battery and cyanide vats 300 metres up river are described as foundations only, both sides of the Alexander River upstream from the crossing. The roaster was erected in 1935, but closed only a year later due to a processing problem. The mine is 740 metres to the south, up a thickly forested and steep ridge, seen from Google Earth as a small clearing.

The site was sampled by CRA in 1988, then Macraes sampled twenty-eight historic trenches, and part of the underground workings, and did some drilling between 1993-1996. Kent Exploration took up the lease in 2009. A 1993 estimate was 4 Mt of ore at 5 g/t amounting to 643,000 ounces, although remains open to question.

Most interest in the mine over recent times, has been the result of two university thesis regarding arsenic and heavy metal contamination at the location. This is Laura Haffert 2005, and K. Malloch 2017. The processing of gold from the arsenopyrite has precipitated arsenolite, phamacolite, yukonite, arsenic bearing hematite, in the Edwards roaster, hardened cement at the battery site, and three small piles of former sludge, variously containing mercury, scorodite, pyrite, minor barite, clay, gypsum, aluminosilicates, quartz, iron oxides, and a Zn-Cu oxide mineral.

Arsenic poisoning is serious, resulting in the vomiting of blood, urine/blood, cramps, convulsions, stomach pain, hair loss, amongst other unsavoury outcomes. It is assumed the material would need to be ingested, which is possible if taking off boots after walking in the area, and not washing hands. The area contaminated amounts to several metres. The studies concluded there is little chance of perceptible levels entering the waterways, as the region's heavy rainfall would dilute the chemicals. The luxuriant vegetation appears to have no trouble, busily taking over the site. It is remote, with few visitors.

However, the New Zealand government allocated 3 million dollars to remove the material from the Alexander Mine, and a similar amount of contaminated material from a fenced off section of the Prohibition battery site at Waiuta. This was planned for the summer of 2016.

Other Regions, Features and Areas containing this locality

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