[Rockhounds] Re: Rockhounds Digest, Vol 43, Issue 34

[Rock Currier]

The last Rattlesnake sand calcites I got I traded with a guy who said he 
worked as a veterinarian in S.D. and that he did work on an Indian 
reservation where the calcites could be collected. He said because of his 
relationship with some of the Indians on the reservation he could collect 
the sand calcites to a limited extent.



The Homestake mine has the deepest mine shaft in the world? Perhaps in the 
USA, but certainly not in the world. http://www.homestaketour.com/ says that 
the lowest mine level at the home stake was "more than 8,000 feet. Gold 
mines in the Rand in the Republic of South Africa have operational levels at 
more than 3.8 km. Some yeas ago I was told by a retired mine captain that 
one mine had an operational level at 15,000 feet below the surface. If I 
recall, the elevation of Joeberg is about the same as Denver. (Plagiarized 
from http://www.mbendi.co.za/indy/ming/gold/af/sa/p0005.htm#5)



      Major Projects


The development of the South Deep Mine (owned jointly by Western Areas and 
Placer Dome). This mine is a southerly extension to the Western Area Gold 
Mine, and contains measured and indicated reserves of 78.9 million ounces of 
gold in 541 million tonnes grading 4.5 g/t gold.

Currently a 2.4 km shaft is being sunk to intersect haulage's developed from 
the Western Areas mine to the north. Avgold are currently developing the 
Target orebody (estimated total resource of 6.5 Moz), situated in the Free 
State Province. Similar to South Deep, the orebody is being accessed by 
haulages developed from Avgold's Lorraine Gold Mine. AngloGold are 
investigating using deep level mining technology to develop the Ultra Deeps 
orebody, situated at 5km depth. The orebody is currently down dip from 
Harmony Gold's Elandsrand mine. (5 km is 16,500 feet)

There is plenty of gold in the ground but the problem is the increasing heat 
encountered at greater depth. Eventually these deposites may be mined only 
by robots which will presumably be better able to take the heat. Sometimes 
the rock simply "explodes" from the pressure.

I think the big open pit copper mine at Chuquicamata, Chile is currently 
3x4.6 km wide and .9 km deep. They advertise their hole in the ground as the 
largest in the world. It depends how you measure it if Bingham is the 
deepest open pit. I think Bingham measures the depth from a mountains side 
where they had some workings. Chuqui is measured from a more or less level 
land surface.

Earth first! We will mine the other planets later.

Rock