|Latitude & Longitude (WGS84):||37° 8' 0'' South , 175° 32' 54'' East|
|Latitude & Longitude (decimal):||-37.13356,175.54849|
|Köppen climate type:||Cfb : Temperate oceanic climate|
Historic gold mine.
100 acres. Located on the south-east side of Karaka Stream. The lowest adit enters from the creek bank.
Originally known as the Karaka Mine from 1891 to 1896, producing 1822 tonnes of ore for 735 ounces of gold. Then the lease was taken over by the Halcyon Gold Mining Company of Auckland covering former leases Halcyon, Ophir, and Manchester. This company erected a battery but when inspected in 1908 the battery had been removed. The Ophir Gold Mining Company operated 1893-1894 producing 93 tonnes of ore.
The country rock is highly propylitised andesite and breccia, with high grade gold where the quartz veins crossed andesite. The quartz veins trend north-east to south-west, or east-west, following the contacts between the andesite and breccia. The quartz veins contain pyrite, chalcopyrite, occasional sphalerite, stibnite and gold. Minor enargite is found. Dark granular pyrite recements disjointed quartz, and also lines cavities, and is found coating the tips of quartz crystals growing within the cavities. Overall the reefs were low grade for gold.
7 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
|Late Pleistocene - Middle Pleistocene|
0.0117 - 0.781 Ma
|OIS5+-OIS2 (Middle Pleistocene - Late Pleistocene) river and hill slope deposits|
Age: Pleistocene (0.0117 - 0.781 Ma)
Stratigraphic Name: Tauranga Group
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.