|Latitude & Longitude (WGS84):||37° 14' 46'' South , 175° 49' 5'' East|
|Latitude & Longitude (decimal):||-37.24623,175.81819|
|Köppen climate type:||Cfb : Temperate oceanic climate|
Historic gold mine.
The mine is located in the upper Wentworth Valley, and can be accessed from the end of the Wentworth Valley Road. The walk includes an impressive waterfall, and a couple of adits next to the track. At the road end is a campground, once the site of the settlement supporting the gold mine.
The mine was worked from 1897 to 1908. Initial development was by the Hauraki Peninsula Exploration Company Limited based in London. With low grade ore found, it spun off the Mananu Gold Mining Company in 1899, to further develop the property. In 1900, a 10 stamp battery and cyanide plant was erected, extended by another 10 stamps in 1901. The mine closed shortly after, re-opened again 1903-1905, then with no capital left was sold to Henry Hopper Adams. He formed the Auckland Gold Mining Company who operated the mine until 1908.
The initial period produced 1002 tonnes of ore for 1369 ounces of gold.
From 1900-1904, the Mananu company produced 7099 tonnes of ore for 9895 ounces of gold; 1905-1908 the Auckland company produced 2774 tonnes of ore for 5992 ounces of gold.
The country rock is altered andesite, with some rhyolite to the north-west and south-east of the old workings. The main reef trends north-east, dipping 70 degrees east. The deposit was accessed by four adits. The upper parts of the reef were richest with gold values decreasing with depth. These near surface parts contained friable oxidised finely crystallised quartz, with some banded curly structures. The veins diminished at depth, being replaced by clay and silicified country rock. The wall rock is coarse textured spotty bluish grey chloritized andesite, with pyrite increasing with depth, found in joint planes. The gold found at the site was fine, and only occasionally visible.
3 valid minerals.
Rock Types Recorded
Select Rock List TypeAlphabetical List Tree Diagram
Entries shown in red are rocks recorded for this region.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
0 - 2.588 Ma
|Cenozoic volcanic rocks|
Age: Pleistocene (0 - 2.588 Ma)
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. 
|Messinian - Tortonian|
5.333 - 11.62 Ma
|Waiwawa Subgroup andesite and dacite (Coromandel Group) of Coromandel Volcanic Zone|
Age: Miocene (5.333 - 11.62 Ma)
Stratigraphic Name: Waiwawa Subgroup
Reference: Heron, D.W. . Geology Map of New Zealand 1:250 000. GNS Science Geological Map 1. 
5.333 - 23.03 Ma
|Coromandel Group Miocene andesite and basaltic andesite lava|
Age: Miocene (5.333 - 23.03 Ma)
Stratigraphic Name: Coromandel Group
Comments: Zealandia Megasequence Extrusive and Intrusive Rocks (Neogene)
Reference: Edbrooke, S.W., Heron, D.W., Forsyth, P.J., Jongens, R. (compilers). Geology Map of New Zealand 1:1 000 000. GNS Science Geological Map 2.