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The effects of a changing gold price on the South African gold mining industryRahn, Friedrich James 01 1900 (has links)
References appear at the end of each chapter / The importance of gold in the development of South
Africa as an industrialised economy cannot be over - emphasised.
Towards the end of the 19th century the economy depended almost
entirely on the production of gold and diamonds which laid the
foundation for a highly - developed national economy.
With gold still continuing to play an important
role coupled with the recent price increases, a need was felt
to investigate the potential effect of higher prices on gold
production in South Africa. For reasons set out in the study,
it was decided to compare potential out put for five different
gold prices. A gold price received by the mines of 050 per
ounce was used as abase. Further calculations were made at
060, 070, 0100 and 0150 per ounce.
The calculations for all the cases were done duri ng
the period when the Rand was floating with the Pound Sterling
and a Rand : Dollar parity of 1:1, 2 4 was used. Since then two
parity changes occured : the Rand was pegged to the Dollar on the 25th October, 1972 to give a Rand : Dollar parity of 1:1,27732, and
the Dollar was devalued on the 13th February, 1973 by
1 1,1 % to give the present Rand : Dollar parity of 1:1, 4192.
The e ffect of the above two parity changes is that
revenue in Dollar terms is overstated by 14,45 5%. It is
suggested that for purposes of this study the Rand figures be
accepted and wherever Dollars are used in future estimates
these be increased by the afore-mentioned 14, 455%. In Dollar terms the five Cases analised will change as follows:
Case A : 5350 becomes 057, 23 per ounce
Case B : 260 becomes 068, 67 per ounce
Case C : 270 becomes 080,12 per ounce
Case D : 0100 becomes 0114 ,46 per ounce
Case E : 0150 becomes 0171, 68 per ounce
To do an in-depth investigation into the effects of
higher gold prices on each individual mine, it was necessary
to analyse the various parameters required in the determination
of gold p r oduction, revenue, lease and tax payments , and
dividends.
For each mine the pay limits at the various gold
prices and at estimated working cost levels, were determined .
Graphs of the estimated tonnages at various pay limits as well
as the average grade of ore mineable at these limits were determined. From these graphs it is possible to obtain the
total tonnage mi neable at various pay limits. Once the foregoing
parameters were obtained for each mine, it was possible
to determine annual gold production, revenue, lease and tax
payments and amounts available to share holders which are
then summarised in tables and illustrated in graphs. For ease of
reference the mines were divided up into
geographica l areas. Gold production revenue, lease and tax
payments to the State and the amounts available to shareholders are
summarised and compared for the various gold prices. The summaries
show bold production remaining fairly constant at or just below
the present level of about 900 000 kilograms per year
until 1978 for Case A,
1979 for Cases B and C,
1983 for Case D, and
1984 for Case E.
before declining progressively thereafter.
Revenue following the same pattern as gold production for
Case A , as is to be expected, but
increasing to a peak of R1 466 million in 1977 for
Case B before progressively declining,
increasing to a peak of R2 434 million in 1982 for
Case D before progressively declining,
increasing to a peak of R3 478 million in 1983 for
Case E but remaining above the 1973 level of R1 254
million until the year 2005.
Lease and tax payments and amounts available to share-holders
following the same pattern as that indicated by
revenue reaching peaks of respectively
R390 million and R268 million for Case B
R485 million and R339 million for Case C
R756 million and R536 million for Case D
R1 000 million and R779 million for Case E.
Following the recent monetary unrest, gold prices
assumed for 1973 are too conservative. Should the present
gold price of about $80 and the 1972 level of production of
909 000 kilograms continue for the remainder of 1973, then
gold production, revenue, lease and tax payments and dividends
as shown for Case C for the year 1975 will be applicable for
1973. This shams gold production of 919 520 kilograms,
gold revenue of R 1690 million,
lease and tax payments of R465 million, and
dividends of R339 million.
The effect of the higher gold price can be clearly
seen when the fore-going figures are compared with the 1971
totals of gold production of 97 6,600 kilogr ams ,
revenue of R396 million from gold,
lease and tax payments of approximately R139 million, and
dividends of R142 million .
Despite a decline in gold production, revenue is expected to
be up by 8 9 % whilst lease and tax payments increase by 2 35%
compared with a dividend increase of 139%.
Finally certain tax concessions to
increase productivity and the rebuy alleviate the labour
shortage,
prolong the li ves of the mines by mining lower grade ore,
and
encourage exploration
was investigated and suggestions made. / Business Management / D. Com.
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Produktiwiteitsverhoging na implementering van 'n multi-vaardighede opleidingsprogram by 'n goudmyn29 October 2014 (has links)
M.Com. (Business Management) / Please refer to full text to view abstract
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Gold veins of the Oatman and Katherine districts, ArizonaLausen, Carl, Lausen, Carl January 1931 (has links)
No description available.
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Population exposure to cyanide vapour from gold mine tailings dams22 June 2011 (has links)
M.Sc. / Atmospheric emissions of dust and chemicals from gold mine tailings are ongoing environmental management issues on the Witwatersrand, where residential areas have developed in proximity to dumps. Residual amounts of cyanide, used as a chemical in the gold extraction process, are deposited with the mineral tailings. This study deals with the evaluation of population exposure to cyanide vapour emitted from gold mine tailings dams, an issue of environmental impact and public health concern. The first part of this study deals with the determination of the emission factors of cyanide vapour from three selected gold mine tailings dams: one under reclamation; one no longer operational; and one fully operational as a slimes deposition site. These three sites are located in the Boksburg area of the Ekurhuleni Metropolitan Municipality. Twelve samples were collected in all: six from the Cason (2628AAL91) mine dump (under reclamation in 2006); four from the ERPM tailings complex [comprising the dormant deposits 4/L/47, 4/L/48, 4/L/49 and 4/L/50, which are north of the N17 national highway; and the 2628ACL1 deposit, which is south of the N17]; and two from the Rooikraal (active) deposition site. All samples were collected in the year 2006. In the second part of the study, the obtained emission factors were used in an Industrial Source Complex dispersion model to measure the degree of population exposure to cyanide vapour for communities that are in proximity to the operational gold mine tailings dams in the Johannesburg Metropolitan Municipality. In the third part, a health risk assessment was carried out for communities in proximity to the selected gold mine tailings dams. The study revealed the average flux (± std. dev.) of Cason to be (4.7 ± 0.8) x 10-7 g m-2 s-1, the average flux of ERPM (3.9 ± 0.6) x 10-7 g m-2 s-1, the average flux of Rooikraal (1.7 ± 0.2) x 10-5 g m-2 s-1. The concentrations of cyanide vapour emitted from the older tailings deposits (sand) that are under reclamation and the dormant slimes dams are very low (and pose little health risk to occupants of adjacent land). However, HCN emission factors from operational tailings dams, which are receiving continuous depositions, are 3 to 80 times higher than the emission factors from dormant mine tailings. Ambient cyanide concentrations near the active tailings deposits may sometimes exceed selected international health standards. The average hourly, daily and annual dispersion model calculations for the Nasrec tailings deposition sites in Johannesburg revealed that 117 938, 18 722 and 8 130 people respectively were exposed to hydrogen cyanide concentrations that were above international (Ontario, Canada) standards. This raises environmental concerns that require institution of cyanide monitoring and setting of emission limits applicable to South African legal and environmental circumstances. These conclusions are based on a small number of emission factor determinations and hence these findings should be regarded as provisional. Further testing and verification are required for emission factors from a larger number of dormant, reworked and active tailings dams.
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Die ontwikkeling en implementering van 'n geïntegreerde begrotingstelsel vir produserende goudmyne23 September 2014 (has links)
M.Com. (Business Economics) / Please refer to full text to view abstract
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Application of hyper-spectral remote sensing to assess contamination associated with gold mining in the Witwatersrand Gold Basin, South AfricaMaya, Mafuza 05 February 2015 (has links)
A research report submitted to the Faculty of Science, University of the Witwatersrand in fulfilment of the requirements for the degree of Master of Science, Johannesburg, August, 2014. / Efflorescent minerals are a common feature of the soil surface in seasonal environments where evapotranspiration (ET) exceeds precipitation (P), and are formed by the evaporation of salt solutions from the soil during periods of drying. On the Highveld gold fields, ET exceeds rainfall by approximately two-and-a-half times during the dry season, and soils overlying acid mine drainage and along polluted stream banks can become covered by distinctively coloured mineral efflorescent crusts. Whereas some efflorescent minerals are relatively insoluble and present a negligible environmental hazard (for example, gypsum), others may be readily soluble and contain high concentrations of potentially toxic metals (for example, copiapite, jarosite and uranyl sulphate). During periods of rainfall, such salts are washed further afield and into surface water bodies and act as sources of episodic pollution.
The presence of some efflorescent minerals can be detected from their characteristic reflectance signatures using remote-sensing (RS) of the electromagnetic spectrum. The species of efflorescent minerals present is a useful indication of the spatial extent of sub-surface contamination, and also of the chemical conditions of the substrate, in particular the concentration of total dissolved solids, pH and redox conditions.
The aim of this study was therefore to assess the use of remote-sensing on indicator efflorescent minerals as a cost-effective aid in the spatial mapping of acid rock-drainage polluted soils and water-bodies. This study describes the range of efflorescent crusts identified on different land-use areas and soil classes in a Highveld gold-mining region. Crusts were first measured in-situ under natural sunlight using a portable analytical spectral radiometer (ASD) as well as using X-ray diffraction (XRD). They were then dissolved in deionized water and the resulting salt solutions allowed to evaporate prior to analysis under controlled lighting conditions. Spectra were post-processed and compared with
iv
geological spectral reference libraries. The salt solutions were also analyzed for metal and sulphate content and the results were used to establish evaporation models from which mineral precipitation could be predicted.
Minerals identified in the visible near-infra red (VNIR) region included iron oxides (hematite and goethite), and the sulphate mineral jarosite. In the short wave infra-red (SWIR) region clay minerals of the smectite group were dominant. Gypsum and Al-Mn-Mg-Na sulphate salts were identified in the SWIR region as mixtures occurring with clay minerals. Minerals identified in the VNIR-SWIR region were all confirmed by X-Ray diffraction (XRD). Upon dissolution, geochemical modeling revealed that gypsum and jarosite are the most common minerals expected to precipitate. The precipitation of gypsum and jarosite indicates persistent acidic conditions after dissolution of mineral salts. Gypsum and jarosite were also accurately identified by hyper-spectral spectroscopy and confirmed by XRD and geochemical modeling. Agreement between spectral interpreted minerals and geochemically precipitated mineral phases demonstrated the ability of hyper-spectral data in detecting efflorescence minerals on the soil surface. Using partial least squares regression (PLSR) combined with bootstrapping, reflectance spectrum was significantly correlated with geochemical variables.
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Rock mechanics aspects of sequential grid miningApplegate, John Daniel January 1991 (has links)
A project report submitted to the Faculty of Engineering,
University, of the Witwatersrand, Johannesburg, in partial
fulfilment of the requirements for the degree of Master of
Science in Engineering
Johannesburg, 1991 / As mining proceeds deeper on Elandsrand Gold Mine scattered mining will no longer be viable due to the excessive stress levels which would occur during mining of the final remnants between raises. Longwall mining with strike stabilizing pillars would eliminate this need for remnant mining. However, since the Ventersdorp contact Reef on Elandsrand has a relatively large number of faults and dykes and highly variable grade, longwall mining would result in a excessive amount of off-reef mining and mining of unpayable reef. / GR 2017
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The geology of the Cam and Motor MineHartman, Louis W. 04 May 2015 (has links)
No description available.
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Placer mining methods and costs in the Circle district, Alaska /Mathews, Raymond T. January 1900 (has links) (PDF)
Thesis (B.S.)--University of Alaska, 1940. / Alaska "Territorial Department of Mines reports" or "TDM reports" are a collection of reports, notes and maps written by Dept. employees working out of several field offices throughout the territory. Series titles and numbers within the collection were retrospectively assigned with the exception of the few written after statehood (1959). Report contains information on the Yukon River Mining Region, Circle Quadrangle. Includes bibliographical references (leaf 80). Also available in electronic format via Internet.
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Yellowknife, N.W.T a study of its urban and regional economy /Bourne, Larry S. January 1963 (has links)
Thesis (M.A.)--University of Alberta, 1963. / Includes bibliographical references (p. [135]-149).
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