·The sequential bio treatment of refractory carbonaceous gold ore is a promising solution to recover gold effectively by environmentally friendly technology which includes bio oxidation of sulfide
·the form of colloidal size grains < µm in carbonates or microcrystalline quartz particles Fleming 1998 Gold recovery from the carbonaceous sulfidic ore is more difficult because the gold is robbed from the cyanide solution by the carbonaceous matter Wan 2001 Table 1 Gold Ore Types and Gold Occurrence
·The Suzdal gold deposit is located in the Western Kalba gold ore belt Eastern Kazakhstan The mineralization is confined to the NE trending tectonic zone that crosscuts Early Carboniferous
·Globally refractory gold occurs in significant proportions in many types of gold deposits The present work reports the occurrence of sulphide hosted refractory gold within the carbonaceous phyllites of the South Purulia shear zone in the Singhbhum crustal province eastern India Detailed textural characteristics paragenesis and trace element concentrations
Generally the carbonaceous gold deposit contains high carbon sulfide ore and graphite and its gold particle size is fine and it has close symbiotic relationship with pyrite and gangue minerals There are two main reasons for the difficult treatment of carbonaceous gold deposits In the process of cyanide gold leaching the carbonaceous
·These spots are large compared to the size of CM grains so it is difficult to retrieve high spatial resolution compositional information on the CM and associated sulfides with this method Fig 1 ; these provide a representative suite of black shale gold ore Associations between sulfides carbonaceous material gold and other trace
Phanerozoic orogenic gold deposits worldwide are commonly considered to be formed from metamorphic devolatilization of marine carbonaceous sedimentary rocks Here we show that the Yindongpo gold deposit from the Qinling orogen central China is genetically associated with the metamorphism of volcanic rocks during the late Paleozoic orogeny which involved the closure
·High gold losses often observed during the cyanidation of carbonaceous gold ores are linked to the inability to separate the ultra fine carbonaceous particles from the gold Adams 2005; Vaughan
·Sequential treatment was applied to carbonaceous Au Ag bearing ore concentrate to maximize the Au and Ag recovery In the preliminary test the present carbonaceous ore had well liberated and exposed type of gold grains which are not refractory but included mainly three types of Ag presented as electrum hessite Ag 2 Te and Ag bearing
·Gold containing ore processing technology has been developed by using chemical X ray phase mineralogical X ray fluorescence analyses The results of experiments on the gold recovery from a concentrate with a particle size of 10 and 4 µm are presented including options for direct cyanidation without preliminary oxygen oxidation as well as with the use of
·Oxidation roasting is one of the most effective methods to remove carbonaceous matter from carbonaceous gold ore However the consolidation of calcine is a common problem caused by a large amount
·Refractory gold ore which shows poor gold recovery by cyanidation typically con tains one or all of the following 1 carbonaceous matter C matter which causes preg robbing; 2 locked gold in sulfides/silicates and 3 cyanide/oxygen consumable matter such as copper or sulfidic material [1 3] The ore used in this study is typical
This study offered fine grained carbonaceous gold ores; the fundamental reason for dressing difficultly And the re search will further provide theoretical and technical guidance to ad vance gold recovery from carbonaceous fine grained gold ores 2 Materials and Methods Samples The carbonaceous fine grained gold ore was obtained from
·A recent Nevada Gold Mines research program focused on pressure oxidation pre treatment of a Carlin type double refractory ore from the Turquoise Ridge Mine The research team found that both arsenian pyrite and carbonaceous matter were highly oxidized within an hour at 300 °C using a bench top autoclave reactor and that the gold recovery from the residues
·Double refractory gold ore contains a higher level of gold than general ore but has been ignored in industry due to economic reasons To improve gold recovery from double refractory gold ore DRGO the sulfides must be oxidized to release gold grains and the carbonaceous matter must be degraded to minimize preg robbing during cyanidation
·A number of studies have been conducted to improve the extraction of gold from fine grained carbonaceous gold ores Nanthakumar et al [3] investigated the microwave roasting process of a double refractory gold ore in which gold is locked in both pyrite and carbonaceous matters They found that it was necessary to keep the temperature of roasting above 650 °C to
·The particle size are variable such as 1 µm to 20 µm The frequency area and volume distribution of these grains indicate liberation inclusion and possible formation of grain clustering Gold grains less than one micron and associated with gangue minerals are potential losses Gold size distribution in different flotation products
·Abstract The Siratur gold deposit occurs in the northern part of the South Uralian segment of the Main Uralian Fault The ore zone of the deposit is confined to an area of a tectonic junction of serpentinites of the Nurali massif and a longitudinal band of carbonaceous schists of the Ordovician Polyakovka Formation which also hosts abundant basalts with
Phanerozoic orogenic gold deposits worldwide are commonly considered to be formed from metamorphic devolatilization of marine carbonaceous sedimentary rocks Here we show that the Yindongpo gold deposit from the Qinling orogen central China is genetically associated with the metamorphism of volcanic rocks during the late Paleozoic orogeny which involved the closure
·Double refractory gold ore was sequentially pretreated to oxidize sulfides by thermophilic archaeon Acidianus brierleyi and then to decompose carbonaceous matters using the cell free spent medium CFSM from white rot fungus Phanerochaete pretreatment by A brierleyi significantly improved the gold recovery from 25% to 77%
·The particle size of carbonaceous gold concentrates was 70% passing a size of −75 μm The carbonaceous gold ore was heating dissolved by H 3 PO 4 1 1 and the amount of carbonate was determined by non aqueous titration In the sample solution after the carbonate was determined
·Xu Xiaoyang of research on leaching process of carbonaceous refractory gold ore[J] Gold Science and Technology 21（1）：82 88 Liu Jiaxiang Wang Guanpu Zhang Zhiyuan 1995 On the separation technology of lead zinc sulfide
·The simplest method of treating a carbonaceous ore is the method described by R W Nice 1971 at the McIntyre Porcupine Mine where the carbon which contains very little gold is floated off and discarded The remaining ore is then responsive to cyanidation This does not work at Carlin because the carbonaceous compounds have a high gold content
·Carbonaceous gold ore as one of the main types of refractory gold ores improving its leaching efficiency is of great significance to the utilization of refractory gold resources In the process of cyanide leaching of carbonaceous gold ore carbonaceous matter could adsorb the gold cyanide complexes in the solution a phenomenon named preg
