With Canadian assistance…
GUYANA Geology and Mines Commission (GGMC) is spending an estimated $64.2M to establish a cyanide laboratory, as part of a wider effort to make high yield mining of lower grade gold a norm in the local industry.
Described as a cyanide technology facility, it will be in GGMC’s Mineral Processing Unit (MPU), which is under construction at the Research and Development Laboratory in Linden.
The immediate thrust of the MPU is piloting and encouraging the improvement of current recovery methods in the local gold and diamond mining sector by developing and testing mineral processing protocols.
After the tests, services will be offered to miners to test their ore and it is planned for the processing equipment to be assembled also as portable units which will be transported into the mining areas to provide a service that would be regarded as applied research activity.
On its completion, the MPU scope of work will be threefold, evaluation of useful minerals in prospecting samples to support geological reconnaissance programmes, production of trial batches of marketable minerals with the objective of attracting potential investors and promoting their industrial ventures and development and testing of gold  processing methods, including cyanidation, to enable local miners to obtain optimum returns from their operations.
The cyanide laboratory is being funded  by the Canadian International Development Agency (CIDA) under the Canadian mining assistance programme, Guyana Environmental Management and Capacity Development Project (GENCAPD).
Speaking about it, a GGMC official said one of its main uses will be to pilot and promote the use of cyanide for leaching at the medium scale level of gold mining operations.
“The application of cyanide technology (cyanide leaching) for the improved recovery of gold from concentrates is expected to result in greater gold recovery overall, particularly of grain sizes that are lost through the conventional sluice box used by miners,” he explained.
Scientists
Two Canadian scientists, Mr. Adrian Daniel and Mr. Rudolfo Neiva de Sousa are in Guyana on assignment to GGMC through GENCAPD, to build the local capacity for gold cyanide leaching in medium scale mining operations.
They are from Acme Analytical Laboratories Limited in Vancouver, British Columbia, the company which won the contract for the GENCAPD undertaking.
de Sousa,  a mining engineer, said: “We are here to set  up equipment and do basic training, so that GGMC can start using their own engineers to discover methods of testing of material to find the best process for optimizing recovery.”
Daniel, a metallurgist, clarified that, although cyanide surrounds the main aspect of their work with the GGMC, their programme has other elements, as well.
“We are also here to show them technologies such as gravity concentration  and flotation which can be used, initially, to process materials and so reduce the mass that goes on to the next step such as cyanide,” he offered.
Daniel continued: “With pre-concentration, you can, conceptually, get down to five per cent of your starting material that would see cyanide leaching. So 95 per cent would not see cyanide, which, from an environmental point of view, is excellent. So we are trying to instill concentration methods of processing first, because you can make much more gains quicker with greater reliability and safety, using such chemicals as cyanide if you pre-concentrate.”
Daniel and de Sousa are also to assist, later, in the setting up of a pilot commercial plant for cyanide leaching of gold at Nine Miles, Mazaruni.
de Sousa disclosed that one of the outcomes of their work with GGMC, to date, has been the creation of a safety committee comprising personnel from GGMC, Linden Fire Service and Linden Hospital.
“Cyanide is like a loaded gun, dangerous but safe if properly handled. So we have a committee and we have the Fire Department and hospital involved and we are addressing valid fears. We are also taking those fears away by showing that cyanide can be safely used for leaching gold,” he informed.
Daniel said they aim to train the GGMC team and leave them working for a short while before auditing what they are doing in the final stage.
Priority
GGMC will be buying equipment for the cyanide laboratory as a top priority with the $64.2M approved by its Board of Directors earlier this month, for the scheduled completion by year end.
Cyanide can recover as much as 95 per cent of the gold in materials being processed and lead to an almost 300 per cent increase in production at the medium scale level as compared to the current method of amalgamation with mercury which, generally, recovers a mere 30 per cent.
However, the officials said the use of cyanide solutions for leaching gold will be restricted to selected medium scale operators who have the wherewithal to operate in that way.
Cyanide makes the cells of an organism unable to use oxygen and its inhalation can lead to a coma with seizures, apnea and cardiac arrest and death in a matter of minutes.
Smaller doses induce loss of consciousness and may be preceded by general weakness, giddiness, headache, vertigo, confusion and perceived difficulty in breathing.
If handled by trained and competent staff, though, the compound can result in a marked increase in gold recovery and production and impact positively on the national production.