VANCOUVER, BC --(Marketwired - January 23, 2017) - East Africa Metals Inc. (TSX VENTURE: EAM) ("East Africa" or the "Company") is pleased to report the final results of a comprehensive metallurgical test program completed for the Terakimti Oxide Gold Project in the Federal Republic of Ethiopia. Column leach testwork achieved gold extractions up to 74.8% with rapid leach rates.
Column Leaching Testwork
The column testwork program was performed to evaluate the potential to utilize heap leaching for the extraction of gold and silver from the Terakimti oxide gold deposit. The column tests included two column leach tests at SGS Mineral Services ("SGS") metallurgical testing facility in Johannesburg, South Africa, and a third column test at McClelland Laboratories Inc. ("McClelland") in Reno, Nevada. SGS and McClelland are highly respected within the global minerals industry for their expertise in metallurgical testing.
Two separate column leach tests at SGS achieved gold extractions of 74.8% and 70.2%. Leach kinetics were rapid with gold extractions of 70% after 14 days and 56% after 15 days respectively. The third column leach test performed at McClelland achieved gold extraction of 73.0% with 70% extraction achieved at 28 days, further supporting the high extraction and good leach kinetics of the Terakimti oxide material. Silver extractions for the two SGS columns were 38.4% and 39.4% respectively and the McClelland column achieved silver extraction of 13.0%.
The two SGS column tests were performed on representative samples of Terakimti gold/silver oxide material crushed to 100% passing minus 16 mm (5/8 inch), a common crush size for heap leaching. The samples were composites of material collected from six metallurgical drill holes in order to represent the different major lithologies identified within the Terakimti oxide gold deposit.
The McClelland column test was performed on coarser oxide material crushed to 100% minus 38 mm (1.5 inch). The material for this test was collected from surface trenches and is considered representative of the near surface zone of the deposit however it may not be representative of the entire oxide deposit. The high level of gold extraction achieved in this test combined with very good leach kinetics, indicates the potential to utilize a coarser crush size for gold extraction at Terakimti.
Additional tests were performed by SGS to assess permeability, mechanical strength and the requirement for agglomeration of the oxide material for heap leaching. The results indicate good permeability and heap material strength, with agglomeration required to maintain permeability in the heap leach. The agglomeration rates applied in the testwork were within ranges typical for heap leaching of oxide gold deposits.
"We are very pleased by the metallurgical test results achieved for the Terakimti oxide and especially the excellent column test results. These positive results confirm that heap leaching technology is the preferred process for the Terakimti oxide gold deposit. The results of this comprehensive testwork program will provide a solid basis for the next stage of project development," stated Sean Waller, P.Eng., Chair of East Africa's Technical Development Committee.
Rock Hardness and Abrasion Tests
Additional testwork performed by SGS included the determination of Bond ball mill work indices and an abrasion index. Three Bond tests were completed generating work indices ranging between 5.5 and 8.7 kwh/t, confirming the Terakimti oxide is soft to very soft relative to other rock types. A single abrasion test generated a low abrasion index of 0.04, indicating this material will have very low abrasiveness. These results are positive as it indicates the oxide material will be relatively easy to crush and will result in low abrasion of crusher wear surfaces.
Kinetic Leach Testwork
The testwork program at SGS also included eighteen kinetic leach tests (bottle roll tests) on representative samples of Terakimti oxide material to assess gold and silver extractions. The resulting extractions at a grind size of 75% minus 75 microns averaged 77.8% for gold. Gold extractions for the five oxide lithologies ranged from 64.9% to 81.2%, with an average of 75.0%. The gold extraction for transition material was 91.4%. Silver extractions for the various lithologies ranged from 20.0% to 77.3%, with an average of 46.9%. The overall gold extractions achieved in the kinetic leach tests may be considered low when compared to typical oxide gold leach operations utilizing agitated leaching. Given that the column leach test extractions are only slightly lower than the kinetic leach extractions, the test results strongly support utilizing heap leaching for the Terakimti oxide gold deposit.
The results of this testwork program will be used to support ongoing evaluation and development of the Terakimti Oxide Gold Project, including plans to initiate a Preliminary Economic Assessment upon closing of the financing announced in East Africa's news release on November 2, 2016.
More information on the Company can be viewed at the Company's website: www.eastafricametals.com.
Sean Waller, P.Eng., FCIM, Director, a Qualified Person under the definitions of National Instrument 43-101, has reviewed and approved the contents of this news release.
On behalf of the Board of Directors:
Andrew Lee Smith, P.Geo., CEO
Cautionary Statement Regarding Forward-Looking Information
This news release contains "forward-looking information" within the meaning of applicable Canadian securities legislation. Generally, forward-looking information can be identified by the use of forward-looking terminology such as "anticipate", "believe", "plan", "expect", "intend", "estimate", "forecast", "project", "budget", "schedule", "may", "will", "could", "might", "should" or variations of such words or similar words or expressions. Forward-looking information is based on reasonable assumptions that have been made by East Africa as at the date of such information and is subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of East Africa to be materially different from those expressed or implied by such forward-looking information, including but not limited to: early exploration; the closing of the agreement with the exploration and development company to advance the Magambazi Project or identify any other corporate opportunities for the Company; mineral exploration and development; metal and mineral prices; availability of capital; accuracy of East Africa's projections and estimates, including the initial mineral resource for the Adyabo, Harvest and Magambazi Projects; estimated exploration licence extensions, interest and exchange rates; competition; stock price fluctuations; availability of drilling equipment and access; actual results of current exploration activities; government regulation; political or economic developments; foreign taxation risks; environmental risks; insurance risks; capital expenditures; operating or technical difficulties in connection with development activities; personnel relations; the speculative nature of strategic metal exploration and development including the risks of diminishing quantities of grades of reserves; contests over title to properties; and changes in project parameters as plans continue to be refined, as well as those risk factors set out in East Africa's management's discussion and analysis for the year end December 31, 2015, management's discussion and analysis for the three and nine months ended September 30, 2016 and East Africa's listing application dated July 8, 2013. Forward-looking statements are based on assumptions management believes to be reasonable, including but not limited to the successful integration of Tigray Resources Inc.'s business with the Company; the price of gold, silver, copper and zinc; the demand for gold, silver, copper and zinc; the ability to carry on exploration and development activities; the timely receipt of any required approvals; the ability to obtain qualified personnel, equipment and services in a timely and cost-efficient manner; the ability to operate in a safe, efficient and effective manner; and the regulatory framework regarding environmental matters, the renewal or extension of exploration licences, and such other assumptions and factors as set out herein. Although East Africa has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking information, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such information will prove to be accurate, as actual results and future events could differ materially from those anticipated in such information. The Company does not update or revise forward looking information even if new information becomes available unless legislation requires the Company do so. Accordingly, readers should not place undue reliance on forward-looking information contained herein, except in accordance with applicable securities laws.
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