Encouraging Gold Extraction Results from Group 11 Technologies Phase 1 Test

Environmentally Friendly Solutions and In Place Mining to Extract Precious Metals

March 15, 2022, Dallas, Texas:  Group 11 Technologies Inc. (“Group 11”) is pleased to announce positive results from the first test in the process to develop In-situ Recovery (“ISR”) of gold using environmentally friendly solutions.  Samples were selected from previously drilled core from the Rattlesnake Hills Gold Project, Wyoming (Rattlesnake Project) which is under option from GFG Resources Inc. (GFG) (GFG-TSXV; GFGSF-OTCQB) to Group 11.  The  gold recovery tests from uncrushed half-core samples demonstrated recoveries ranging from 15.9% to 77.5%, averaging 48.2% using a non-cyanide solution. Bottle roll testing of crushed and ground material returned gold recoveries ranging from 38.3% to 89.5%, averaging 61.4% using a non-cyanide solution.  Group 11 is working to develop and prove the process for ISR of gold and other metals.  EnviroMetal Technologies Inc. (EnviroMetal) (ETI-CSE) was engaged to conduct this initial test work using its proprietary and environmentally friendly chemistry on existing core samples selected by Group 11 personnel  from the Rattlesnake Project. These samples were selected to cover a maximum range of gold bearing rock types and gold grades present in the Rattlesnake Deposit.   

Dr. Dennis Stover, Chief Technical Officer of Group 11 Technologies and enCore Energy Corp. and co-discoverer of the in-situ recovery process in the uranium sector said: “Group 11 is very pleased with the initial tests which have shown strong results to extract gold from the existing core sample with an environmentally friendly solvent. This first step will provide the basis for future tests to be conducted on the use of the lixiviant in combination with ISR technology. Group 11 is working to create new environmentally-friendly options to extract gold and other metals through less invasive ISR extraction which is in widespread use in  the uranium sector.”


Group 11 Technologies and their partners will host a webcast on Thursday, March 17 at 11:00 am Eastern Time (8:00 am Pacific Time) to discuss the results of the Phase 1 tests, next steps and to answer any questions from shareholders. Shareholders, analysts, investors, and media are invited to join the live webcast by registering using the link below. A replay of the webcast will be available.

Please join us: https://attendee.gotowebinar.com/register/8133997228348689164


Group 11 selected 17 half-core and 22 composite core chip samples from the Rattlesnake Project with the objective of evaluating gold recovery and leach kinetics to provide baseline data for future studies focused on in-situ leaching using EnviroMetal’s environmentally superior leach chemistry.


The half core samples were leached whole and uncrushed  in ETI’s lixiviant at 28% – 45% pulp density for 22 to 92 days, at a neutral pH, to investigate gold recovery for ISR application. Gold recoveries ranged from 15.9% to 77.5%, averaging 48.2%.  These samples were tested whole without crushing to more closely emulate expected results from an ISR environment.

Select Samples of Uncrushed Half-Core Leach Testing

 Gold Grade (g/t)  
Test NumberCalc. HeadPulp Density %Leach Time (days)Gold Recovered (%)
HE108 HE1151.31 2.3040.7 38.528.1 23.034.1 77.5

Recovery Curves of Uncrushed Half-Core Leach Testing


The rock samples were crushed to -2.5 mm and tested via bottle roll methodology with ETI’s lixiviant at 30% pulp density for 9 to 28 days at a neutral pH to investigate gold recovery. Gold recoveries ranged from 38.3% to 89.5%, averaging 61.4%.  Leaching with the bottle roll on crushed material provided faster kinetics and higher recoveries, as would be expected, due to the increased surface area exposed to the solution.

Select Samples of Crushed Core Bottle Roll Test Results

Gold Grade (g/t)  
Test NumberCalc. HeadAssayedLeach Time (days)Gold Recovered (%)
HE207 HE2162.49 0.872.48 0.7210 1038.6 89.5

Recovery Curves of Bottle Roll Testing

Although not directly comparable due to significantly different testing parameters, these bottle roll test results compare favorably with traditional bottle roll results from testing conducted in 2009 by Resource Development Inc. (RDI) for the Rattlesnake Project.  The RDI testing utilized cyanide with 1g/l of NaCN, a pH of 11, 40% solids, 72 hour leaching time and a very fine grain size of 80% less than .074mm.  Gold recoveries ranged from 13.7% to 65.4%, averaging 43.4% from 15 composite drill core samples.

With the results of the first test in hand, Group 11 will proceed with ISR analysis and a thorough review of field data and leach test results to determine next steps which may include additional laboratory tests; additional drill tests and permitting.


Splits of the crushed head samples and leach tails from the 22 bottle roll tests as well as the tails from the 17 half core leach tests were analyzed by MSALABS, an independent lab based in Langley, British Columbia.

The Rattlesnake Hills Gold Project

Group 11 Technologies and GFG Resources Inc. (GFG-TSXV; GFGSF-OTCQB) entered into a joint venture agreement in April 2021 to consider the Rattlesnake Project in Wyoming as a test project for the potential of ISR technology for the extraction of gold and other metals.  Wyoming has a well-established regulatory process and necessary legislation for ISR technology and the Rattlesnake Project, with over USD$40 million in drilling and extensive data, offers a variety of mineralized settings providing excellent testing parameters for ISR using a non-cyanide and environmentally-friendly solution.

About EnviroMetal Technologies Inc. (ETI-CSE)

EnviroMetal Technologies Inc. is engaged in the development and commercialization of environmentally friendly formulas and technologies for the treatment of materials in the primary and secondary metals industries. EnviroMetal Technologies Inc. has developed an alternative lixiviant to cyanide for leaching gold which is both effective and non-toxic. Using its proprietary non-cyanide, water-based, neutral pH treatment process EnviroMetal extracts precious metals from ores, concentrates, and electronic waste. A key differentiator of EnviroMetal’s technology is the ability to regenerate its lixiviant chemically in a low-cost, sustainable closed-circuit process. This process results in extended reusability of both the reagent and the process water. The process also produces little to no wastewater and reduces wastewater treatment requirements. In contrast, other reagents such as cyanide require detoxification treatment before disposal.

About Group 11 Technologies Inc.

Group 11 Technologies Inc. is led by a group of technical pioneers and experts in the development and application of in-situ recovery (“ISR”) with significant experience operating in the United States. Group 11’s goal is to combine ISR, a non-invasive extraction technology, with an environmentally friendly water-based chemistry to recover gold and other metals, providing an alternative development path to conventional open pit and underground mineral extraction.  The combination of in-situ recovery extraction (ISR) technology and environmentally friendly water based chemistry to recover gold and other metals provides a promising alternate solution to conventional open pit and underground mineral extraction. The goal of advancing sustainable extraction considers growing concerns surrounding water use and discharge, carbon footprint, energy consumption, community stakeholders and workplace safety while addressing a growing global need for metals in our daily lives.  

Group 11 is a group of elements in the periodic table, also known as the coinage metals, consisting of gold (Au), silver (Ag) and copper (Cu).  

For additional information:
Group 11 Technologies Inc.

Janet Sheriff, President
[email protected]

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This news release includes certain forward-looking statements within the meaning of applicable securities laws including transactions and other properties, and the potential advancement thereof. Forward- looking statements are statements that relate to future, not past, events. In this context, forward- looking statements often address expected future business and financial performance, and often contain words such as “anticipate”, “believe”, “plan”, “estimate”, “expect”, and “intend”, statements that an action or event “may”, “might”, “could”, “should”, or “will” be taken or occur, or other similar expressions. Estimates of mineral resources and reserves are also forward looking statements because they constitute projections regarding the amount of minerals that may be encountered in the future. All statements, other than statements of historical fact, included herein including, without limitation; statements about the terms and completion of the transaction are forward-looking statements. By their nature, forward-looking statements involve known and unknown risks, uncertainties and other factors, which may cause the actual results, performance or achievements, or other future events, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Forward-looking statements are made based on management’s beliefs, estimates and opinions on the date that statements are made and the respective companies undertakes no obligation to update forward-looking statements if these beliefs, estimates and opinions or other circumstances should change, except as required by applicable securities laws. Investors are cautioned against attributing undue certainty to forward-looking statements.

In-Situ Recovery (ISR) Technology

The In-Situ Recovery (ISR) process is a metals recovery process which differs dramatically from conventional mining techniques.  Unlike conventional open pit and underground mining, ISR employs only a series of water wells.   A dilute groundwater-based solution is injected into the mineral bearing zone to selectively dissolve the target mineral.  The solution is then recovered and this mineral rich solution is then sent to a recovery facility much like a standard commercial water treatment plant for mineral recovery.  The now barren solution is repeatedly recycled to the wells with ground water consumption kept to an absolute minimum.  At completion of “mining”, this ground water is restored and suitable for all uses it had prior to mining, all wells are plugged, and the land is useable for all its pre-mining uses (farming, pasture lands, etc).

The ISR process was first tested for production of uranium in the mid-1960s and was first applied to a commercial-scale project in 1975 in South Texas. Many of the Group 11 technical team now working to apply the technology to gold and other metals  were actively involved.  All environmental disturbances are short term and there is no excavation of significant quantities of rock and ore, no open pits, no tailings facilities and absolute minimal liquid and solid waste.  It is environmentally benign compared with conventional methods and generally more cost effective.  At present, 50% of all global uranium mining is conducted with the ISR process.

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