Final Results from Farallon's Metallurgical Test Program Confirm Precious Metals Recoveries for Campo Morado.VANCOUVER, British Columbia British Columbia, province (2001 pop. 3,907,738), 366,255 sq mi (948,600 sq km), including 6,976 sq mi (18,068 sq km) of water surface, W Canada. Geography -- Farallon Resources Ltd. (TSX TSX Toronto Stock Exchange (TSE before April, 2002) TSX Transfer from Stack Pointer to Index TSX True Space Extension :FAN) - Current Studies Assessing G-9 Deposit and Lead Recoveries Dick Whittington Not to be confused with Sweet Dick Whittington. Dick Whittington (also Dick Wittington) is a character in a British pantomime, very loosely based on Richard Whittington, who was probably born in Gloucestershire but whose family came from Kinver in Staffordshire, , President and CEO (1) (Chief Executive Officer) The highest individual in command of an organization. Typically the president of the company, the CEO reports to the Chairman of the Board. of Farallon Resources Ltd. is pleased to announce that the final report from the successful metallurgical met·al·lur·gy n. 1. The science that deals with procedures used in extracting metals from their ores, purifying and alloying metals, and creating useful objects from metals. 2. "proof of principle" pilot plant test program has now been completed. This final report covered confirmation and optimization tests, focusing on the recovery of precious metals Precious Metals Valuable metals such as gold, iridium, palladium, platinum, and silver. Notes: Investing in precious metals can be done either by purchasing the physical asset, or by purchasing futures contracts for the particular metal. and lead from the autoclave autoclave Vessel, usually of steel, able to withstand high temperatures and pressures. The chemical industry uses various types of autoclaves in manufacturing dyes and in other chemical reactions requiring high pressures. residue and the reduction of lime and cyanide cyanide (sī`ənīd'), chemical compound containing the cyano group, -CN. Cyanides are salts or esters of hydrogen cyanide (hydrocyanic acid, HCN) formed by replacing the hydrogen with a metal (e.g., sodium or potassium) or a radical (e.g. consumption used in the process. The results of the latest report have confirmed the gold and silver recoveries announced earlier (News Release dated September 12, 2005) and confirmed that potential exists to lower lime and cyanide consumption. Extraction of lead from the autoclave residues was not successful in this series of tests and will be the focus of further studies being carried out in conjunction with optimizing the complete flowsheet design. The results of the latest testwork are summarized below. The testing involved lime boil of the autoclave residues, followed by cyanidation at different sodium cyanide sodium cyanide n. A poisonous white crystalline compound, NaCN, used in extracting gold and silver from ores and in dye manufacture. Noun 1. addition levels (0.5 to 1.5 g/L) and either 12, 24 or 48 hours of total leaching. An initial series of tests on Naranjo residue produced during the PARTOX(TM) pilot campaign indicated that, compared to the previous results of the pilot plant program, lower lime additions (71-73 kg/t of feed to cyanidation), lower cyanide concentrations (0.5 - 1.0 g/L of NaCN) and shorter times (12-24 hours) could be applied without loss of precious metal extraction. The results of these initial tests indicated gold extraction Gold extraction or recovery from its ores may require a combination of comminution, mineral processing, hydrometallurgical, and pyrometallurgical processes to be performed on the ore. rates ranging from 49.5 to 57.6% and silver extraction rates ranging from 77 to 88.6%. Based on these promising results, three further tests were performed on residues from El Largo Largo, town (1990 pop. 65,674), Pinellas co., W Fla., on the Pinellas peninsula and the Gulf Coast, across the bay from Tampa; settled 1853, inc. 1905. It is a packing, canning, and shipping center in a citrus fruit and fishing area. , Naranjo and Reforma. These tests returned similar ranges of gold and silver recovery with 24 hours of leaching at reduced cyanide and lime reagent reagent /re·a·gent/ (re-a´jent) a substance used to produce a chemical reaction so as to detect, measure, produce, etc., other substances. re·a·gent n. consumptions as follows:
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Reagent
Consump- % Overall
NaCN tion % Recovery
Deposit Time Addition kg/t of Recovery Residue Lime Boil
Sample Hours g/L CN Feed 24h g/t + CN
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CaO+ Au Ag Au Ag Au Ag
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El Largo 24 1.0 90.1 41.0 78.6 0.60 28.7 44.0 78.7
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Naranjo 24 1.0 73.6 51.2 76.7 0.76 25.7 52.6 76.8
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Reforma 24 1.0 56.2 49.0 74.0 0.69 23.2 50.7 74.1
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Farallon previously announced the successful completion of the Pilot Plant test program, which confirmed that a bulk flotation/hydrometallurgical process approach could successfully recover the four major metals - zinc, copper, gold and silver - from the mineralization Mineralization The process by which the body uses minerals to build bone structure. Mentioned in: Rickets mineralization, n the bioprecipitation of an inorganic substance. at the Campo Morado Project. The Company trademarked the process under the name "PARTOX(TM)" and intends to market it to prospective projects in due course; however, using these results to calculate the necessary capital and operating cost estimates required for completion of a Pre-Feasibility Study for the Campo Morado Project is the current priority. These results and those announced above and previously, refer to the Reforma, Naranjo and El Largo deposits. The recent discovery at G-9 (News Releases dated June 6, 2005; September 26, 2005; October 12, 2005 and November 7, 2005) has not yet been evaluated for its potential to be treated by hydrometallurgy hydrometallurgy Extraction of metal from ore by dissolving the metal (as one of its salts) and then recovering it from the solution. The operations usually involved are leaching (dissolving in water), commonly with additional agents; separating the waste and purifying the ; however, hydrometallurgical hy·dro·met·al·lur·gy n. The treatment of metal or the separation of metal from ores and ore concentrates by liquid processes, such as leaching, extraction, and precipitation. testwork will also be carried out in conjunction with the Preliminary Economic Assessment, currently underway, that includes the high grade G-9 deposit. These tests will enable G-9 to be integrated into the mine development plan as the first deposit to be mined with the necessary degrees of engineering confidence. A summary of the PARTOX(TM) process, including the results of the successful Pilot Plant program, is attached along with a simplified processing flowsheet. Dick Whittington said: "I'm pleased that we have already seen the benefits of the first round of optimization work on the PARTOX(TM) process flowsheet and use of consumables. This is an exciting process that will enable us to unlock all of the key metals in the deposits discovered to date. The work planned for G-9 will enable us to integrate G-9, seamlessly, into the mine development plan and quickly enable us to recommence Re`com`mence´ v. i. 1. To commence or begin again. 2. To begin anew to be; to act again as. He seems desirous enough of recommencing courtier. - Johnson. v. t. 1. To commence again or anew. the Pre-Feasibility study that is on hold, pending the completion of the G-9 work. We are now focused on optimizing the work done to date and will have further results next year as our program unfolds." The metallurgical program is supervised by independent consultants that are qualified persons. David Dreisinger, P.Eng., is responsible for the hydrometallurgical program and Peter Taggart, P.Eng., is responsible for the flotation testwork and ensuring that bulk concentrates are developed. Farallon has a strong cash position of $10.6 million that will enable the Company to complete its current drilling program and conclude a Preliminary Assessment of the project in early 2006. For further details on Farallon Resources Ltd. and its Campo Morado property, please visit the Company's website at www.farallonresources.com or contact Investor Services at (604) 684-6365 or within North America North America, third largest continent (1990 est. pop. 365,000,000), c.9,400,000 sq mi (24,346,000 sq km), the northern of the two continents of the Western Hemisphere. at 1-800-667-2114. ON BEHALF OF THE BOARD OF DIRECTORS J.R.H. (Dick) Whittington, President & CEO Forward-Looking Information This release includes certain statements that may be deemed "forward-looking statements forward-looking statement A projected financial statement based on management expectations. A forward-looking statement involves risks with regard to the accuracy of assumptions underlying the projections. ". All statements in this release, other than statements of historical facts, that address future production, reserve potential, exploration drilling, exploitation activities and events or developments that the Company expects are forward-looking statements. The likelihood of future mining at Campo Morado is subject to a large number of risks and will require achievement of a number of technical, economic and legal objectives, including obtaining necessary mining and construction permits, completion of pre-feasibility and final feasibility studies, preparation of all necessary engineering for pits and processing facilities as well as receipt of significant additional financing to fund these objectives as well as funding mine construction. Such funding may not be available to the Company on acceptable terms or on any terms at all. There is no known ore at Campo Morado and there is no assurance that the mineralization at Campo Morado will ever be classified as ore. For more information on the Company and the risk factors inherent in its business, investors should review the Company's Annual Information Form at www.sedar.com. SUMMARY OF CAMPO MORADO HYDROMETALLURGICAL PILOT PLANT PROGRAM RESULTS USING THE PARTOX(TM) AUTOCLAVE LEACH AND ATMOSPHERIC COPPER LEACH PROCESS The PARTOX(TM) Process has been developed to extract copper, zinc, gold and silver from the Campo Morado deposit of Farallon Resources Ltd. The process of metal recovery starts at the underground mine with excavation of valuable mineralized min·er·al·ize v. min·er·al·ized, min·er·al·iz·ing, min·er·al·iz·es v.tr. 1. To convert to a mineral substance; petrify. 2. To transform a metal into a mineral by oxidation. 3. rock, containing a variety of sulphide minerals and metal values. The rock is to be transported to the surface and then to the mill. At the mill proposed for the Campo Morado Project, the rock will be crushed and ground to fine size (finer than beach sand) to expose the valuable minerals. The ground rock will then be subjected to flotation, a well known process in mineral separation, where the desirable and valuable minerals, containing copper, zinc, gold and silver, are floated and recovered as a concentrate. The remaining barren material is rejected and is placed in a waste pond A waste pond or chemical pond is a small impounded water body used for the disposal of water pollutants, and sometimes utilized as a method of recycling or decomposing toxic substances. at the site. The PARTOX(TM) Process is a hydrometallurgical process that allows for separation and recovery of valuable metals from Campo Morado concentrate. Hydrometallurgy is a term that refers to chemical processes carried out in water based solutions. There are six steps in the PARTOX process as follows: Step 1: Autoclave Leaching of Concentrate The first step in the process is to use an autoclave leach process (at 150 degrees C) for partial oxidation In chemistry, a partial oxidation reaction occurs when a substoichiometric fuel-air mixture is partially combusted in a reformer, creating a hydrogen-rich syngas, which can then be put to further use, for example in a fuel cell. (PARTOX(TM)) of the bulk concentrate. This process can be compared to a pressure cooker in which the minerals of value "break down" and allow zinc and copper to be put into solution. The minerals that contain gold and silver are also altered to allow subsequent extraction of precious metals by the well known cyanidation process. The hot slurry slurry, n a thin mixture of insoluble material floating in liquid. slurry solids in suspension. Used as a method of feeding pigs—slurry is pumped through fixed lines and delivered to troughs by hoses equipped with gasoline pump fittings. released from the pressure cooker is allowed to continue to leach in a series of tanks open to the atmosphere. This has a particular benefit in increasing copper extraction Currently, the most common source of copper ore is the mineral chalcopyrite (CuFeS2), which accounts for about 50% of copper production. The focus of this article is on the process of copper extraction from chalcopyrite ore into pure metal. and, hence, is referred to as the "copper leach". Step 2: Counter Current Decantation decantation /de·can·ta·tion/ (de?kan-ta´shun) the pouring of a clear supernatant liquid from a sediment. decantation the pouring of a clear supernatant liquid from a sediment. (CCD CCD in full charge-coupled device Semiconductor device in which the individual semiconductor components are connected so that the electrical charge at the output of one device provides the input to the next device. ) After dissolving copper and zinc into solution, the next challenge is to separate the valuable solution from the solids that are depleted de·plete tr.v. de·plet·ed, de·plet·ing, de·pletes To decrease the fullness of; use up or empty out. [Latin d in copper and zinc (and still contain gold and silver). The method selected for Campo Morado is to use a Counter Current Decantation (CCD) circuit. This circuit uses the principles of gravity settling to wash the solids in 7 stages. The washed solids (residue) go to the precious metal recovery process and the solution to copper and zinc recovery process. For the pilot plant, seven stages of CCD washing were applied to give 99.9% overall washing efficiency for copper and zinc. Step 3: Copper Solvent Extraction Solvent extraction A technique, also called liquid extraction, for separating the components of a liquid solution. This technique depends upon the selective dissolving of one or more constituents of the solution into a suitable immiscible liquid solvent. and Electrowinning (SX/EW) Approximately 25% of the copper currently obtained from mines world-wide is recovered by the copper solvent extraction and electrowinning (SX/EW) process. Solvent extraction would selectively extract copper from the Campo Morado leach solution and transfer the copper to a second solution, from which copper is recovered by electrolysis electrolysis (ĭlĕktrŏl`əsĭs), passage of an electric current through a conducting solution or molten salt that is decomposed in the process. . The copper that is electrolysed is highly purified - over 99.99% pure copper. It is expected that the copper SX/EW product from Campo Morado will meet or exceed LME See London Metal Exchange. LME See London Metal Exchange (LME). Grade A/Comex Grade 1 purity specifications, as is normally the case for such operations. Step 4: Iron Removal After copper recovery, the solution advances to zinc recovery. Prior to zinc recovery, iron is removed by adding limestone and air to create the conditions for precipitation of iron without loss of zinc. This step was tested in the Campo Morado pilot plant with 99.9% efficiency. As a result less than 10 parts per million parts per million mg/kg or ml/l; see ppm. of iron is present in the feed to the zinc recovery process. Losses of both copper and zinc to the iron precipitate precipitate /pre·cip·i·tate/ (-sip´i-tat) 1. to cause settling in solid particles of substance in solution. 2. a deposit of solid particles settled out of a solution. 3. occurring with undue rapidity. were negligible. Step 5: Zinc Solvent Extraction and Electrowinning (SX/EW) Zinc solvent extraction is increasing in importance as a technical route for primary zinc recovery. The Skorpion plant of Anglo American Base Metals in Namibia now recovers 150,000 tonnes per year of zinc by SX/EW. This same process is to be used on the iron-free solutions at Campo Morado, as referred to above. During the Farallon pilot plant testing, a total of 102 kg of zinc metal cathode was produced, with a greater than 99.99% zinc purity. It is expected that the zinc cathode product from SX/EW process at Campo Morado will meet or exceed "Special High Grade (SHG SHG Second Harmonic Generation SHG Short-Handed Goals (hockey) SHG Self Help Group SHG State History Guide (formerly State House Girls) SHG Sacred Heart Griffin )" Grade purity specifications, as is normally the case for such operations. Step 6: Gold and Silver Recovery The standard method practised around the world for gold recovery is cyanide leaching, and this same process is proposed for Campo Morado. Washed autoclave residue is treated by a series of chemical steps to extract and recover gold and silver. The final product is a mixed "alloy" of gold and silver (in a bar called a dore) that is sent to a refinery for final separation into high purity gold and silver. For the pilot plant, the average gold extractions were 57%, 66% and 62% for samples from Naranjo, Reforma and El Largo, respectively. The comparable average silver extractions were 82%, 76% and 88% for the same sample series. Overall Results: The Pilot Plant program was a significant success, proving that hydrometallurgical extraction processes, and in this case the PARTOX(TM) process, work on Campo Morado mineralization. The pressure oxidation and copper leach cumulative recoveries achieved for the pilot plant are summarized below.
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Cumulative
Concentrate Process Step Extraction (%)
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Zn Cu Fe
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Naranjo Pressure Oxidation (POX) 98 84 16
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POX + Copper Leach 98 88 16
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Reforma Pressure Oxidation (POX) 92 69 21
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POX + Copper Leach 93 71 18
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El Largo Pressure Oxidation (POX) 98 83 22
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POX + Copper Leach 98 87 13
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POX + Copper Leach 98 87 13
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Average for all Feeds Pressure Oxidation (POX) 96 79 20
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POX + Copper Leach 96 82 16
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To view the diagram accompanying this press release please click on the following link: http://www.ccnmatthews.com/docs/fanfig.jpg No regulatory authority Noun 1. regulatory authority - a governmental agency that regulates businesses in the public interest regulatory agency administrative body, administrative unit - a unit with administrative responsibilities has approved or disapproved the informatio n contained in this news release. Farallon Resources Ltd. (TSX:FAN) |
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