Golden Bar Mine, Wakamarina Goldfield (Canvastown), Marlborough Region, New Zealandi

Regional Level Types
Golden Bar Mine	Mine
Wakamarina Goldfield (Canvastown)	Ore Field
Marlborough Region	Region
New Zealand	Country

The lode can be traced for 1.8 kilometres, averaging 2 metres wide, although only 818 metres was worked, and overall it is low grade in gold and scheelite. The mine is the largest in output for the Marlborough Province at 599 kg of gold, and 389 tonnes of scheelite from 101 357 tonnes of quartz.

The lode is 0.6 to 2.4 metres thick, with a steep dip to level 2 at 122 metres. The richest gold was found adjacent to a 70 degree south-west dipping fault towards the southern end of the lode. Most of the lode however occupies a 70 degree north-east dipping normal slip fault. The lode is 96% quartz, sulphide poor, 1% scheelite mainly near the Footwall.

Ribbon banded quartz lodes fill tensional faults of the Marlborough Schist, and Wakamarina Quartzite filling a steep dipping normal fault, with vertical quartz-scheelite veins, containing minor gold, with secondary pyrite adjacent.

The quartzite comes in pink, red, yellow, green, and white colours, with thin interbedded sandstone, and siltstone, associated with metabasites and metagabbro. The quartzite is seamed by quartz-calcite-scheelite-adularia veins. The quartzite contains abundant stilpnomelane, pumpellyite, tiny pink spessartine garnets, and rare ferroaxinite, cross-cut by quartz-albite-pumpellyite-sericite-illite-adularia veinlets.

Metapsammites contain plagioclase, orthopyroxene, hornblende, and titanite. The schist contains quartz, chlorite, albite, sericite, pumpellyite, stilpnomelane, titanite, prehnite, colourless actinolite, biotite like hydromica, and rare clinozoisite.

Metabasites are fine grained with augite-titanite-plagioclase, with metagabbro interlayered in the quartzite, showing anomalous dark blue chlorite, pumpellyite, stilpnomelane, illite, and minor calcite, epidote, and actinolite.

The Footwall consists of pumpellyite-actinolite psammitic schist, while the Hanging Wall is stilpnomelane-pumpellyite-spessartine quartzite and metabasites.

There were five deformation events. The first being early Jurassic, third mid Jurassic, and fifth all produced minor quartz-scheelite veining, while the fourth created tensional faults across mylonites with local deposition of more major quartz-scheelite-gold lodes.

There is an extensive alteration zone of sericite and K-feldspar, but poor in pumpellyite, stilpnomelane, and actinolite. Marcasite is found locally with pyrite, while chalcopyrite was found in one lense as minor grains. One vein was located with knots of pyrrhotite and pyrite, with minor chalcopyrite. Sparse gold grains were found adjacent to the pyrite. Overall the lode is sulphide poor, and low grade for gold. Quartz in the lode contains microscopic fluid inclusions.

The lode was discovered in 1881, but its low grade caused little activity until scheelite prices rose around 1910. At this point the Dominion Consolidated Company, combined various leases along the lode, and began systematic mining until the company was liquidated in 1923. Later attempts to re-open the mine across 1925-1926, 1930's and 1940's were unsuccessful.

Other Regions, Features and Areas containing this locality

References