Alexandra Antimony Mine, Alexandra, Central Otago District, Otago Region, South Island, New Zealand
|Latitude & Longitude (WGS84):||45° 15' 17'' South , 169° 22' 44'' East|
|Latitude & Longitude (decimal):||-45.25473,169.37902|
|Köppen climate type:||Cfb : Temperate oceanic climate|
A vein of stibnite was exposed on the banks of the Clutha River, opposite the Alexandra town site, and 300 metres up river from the bridge.
It was known from the early days of the gold rush, but only investigated in 1900, by Blair and Miller (surnames) who sank a shallow shaft close to the river bank, and dug cross trenches.
The lode is a small north-east striking stibnite bearing lode. A collector reports on the site in 1974, being the early days of collecting when specimens were available. It is unclear the present status of the site, being close to urban development.
The site shows as a crumbly quartz vein in mica schist, trending north north-east, and dipping 45 degrees west north-west. The stibnite is found in short irregular bands. The workings were not accessible in 1974, and the mullock pile was dug over. Surface and near surface specimens were covered by a yellow oxide coating of cervantite, and rarer valentinite. Scraping away the coating reveals the metallic stibnite, lustrous, but dulls over the years when exposed. Only cleavage faces show, up to 4 cms.
(Watson, 1974) recommends finding a large chunk with quartz veins, which may contain cavities with stibnite crystals. Specimens are described where stibnite crystals alter course across the cavities to avoid quartz crystals.
Specimens of this quality still available at the site now is unlikely.
4 valid minerals.
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 - 0.0117 Ma
|OIS1 (Holocene) mining waste|
Age: Anthropocene (0 - 0.0117 Ma)
Comments: Holocene human-made deposits. Age based on known
Reference: Heron, D.W. . Geology Map of New Zealand 1:250 000. GNS Science Geological Map 1. 
201.3 - 252.17 Ma
|Caples Group TZIII schist|
Age: Triassic (201.3 - 252.17 Ma)
Stratigraphic Name: Caples Group
Comments: Eastern Province (Caples Terrane) Rocks
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. 
|Triassic - Permian|
201.3 - 298.9 Ma
|Paleozoic-Mesozoic crystalline metamorphic rocks|
Age: Phanerozoic (201.3 - 298.9 Ma)
Stratigraphic Name: Haast Schist
Comments: Caples Terrane
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.