Fireweed Commences Metallurgical and Ore Sorting Test Work on Boundary Zone
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NEWS RELEASE
May 18th, 2021 TSXV: FWZ
Fireweed Commences Metallurgical and Ore Sorting Test Work on Boundary Zone
Vancouver, British Columbia: FIREWEED ZINC LTD. (“Fireweed”) (TSXV: FWZ) is pleased to
announce the start of a metallurgical test program at Boundary Zone that includes both traditional methods
and ore-sorting — an innovative and proven technology deployed at many mines worldwide to upgrade
mill-feed at low cost . Boundary Zone is an advanced exploration prospect with widespread zinc
mineralization occurring at surface and in drill holes, 15 km west of Fireweed’s Jason Zn -Pb-Ag deposit,
Macmillan Pass, Yukon, Canada.
Highlights
• Metallurgical test work has been commissioned on both ore-sorted and unsorted samples.
• Composites from a one-tonne sample have been crushed and screened and coarser fractions will be
tested on a full-scale multi-sensor ore sorter.
• X-Ray Fluorescence (XRF) sorting has previously shown promising upside at Boundary Zone and
this test work will better quantify the potential benefits.
CEO Statement
Brandon Macdonald, CEO, stated “This is an important step forward in realizing the economic potential of
Boundary Zone. This is the first metallurgical test work conducted on Boundary Zone and will complement
the metallurgical data we have on our Tom and Jason deposits. The full-scale ore sorting tests will determine
if there is potential to increase mill feed grades while simultaneously improving grinding costs. The sorting
tests on bulk samples using full-scale sorting equipment will be more robust than the bench-scale test work
conducted in 2019. Flotation and grinding test work are being carried out on sorted and unsorted material
to support both possible processing scenarios. Together, the metallurgical and sorting test work will give
Fireweed holistic insight to help optimize the processing flowsheet for the Macmillan Pass project.”
Boundary Zone Ore Sorting and Metallurgical Test Work
Two identical 1.2 tonne samples of quartered drill core were taken from holes NB19-001 and NB19-002 at
Boundary Zone Main for a total of 2.4 tonnes of material. This will allow direct comparison of two streams
of test work, using one sample for ore sorting and the other sample for unsorted flotation and grinding tests.
Both samples have been subdivided into the same nine separate composites representing the range of grade
profiles, mineralization styles and host rocks present at Boundary Zone Main. The composites selected for
ore sorting ha ve been crushed and screened, sized from 0.5” to 2” (13 to 50 mm) with the fines being
collected for subsequent testing. Over 600 kg of screened composite material have been selected for ore
sorting from one of the 1.2 tonne samples of quarter drill core . The remaining ~600 kg comprises high
grade composites and waste rock composites. High -grade composites will not be tested for ore sorting to
avoid potential metal losses during sorting. Waste composites will not be tested for ore sorting although
appropriate lengths of adjacent waste material have been included in sorted composites to account for
mining dilution.
Ore sorting test work is being conducted by Steinert, a leading producer of sorting technology for the mining
and recycling industries, at their test facility in Germany. Samples have arrived in Germany and the sorting
trial will be completed in June. A range of sensors will be tested including X-Ray Transmission (XRT), X-
Ray Fluorescence (XRF), optical colour, laser surface, and electromagnetic induction. Previous bench-scale
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ore sorting test work indicated that Boundary Zone material responded well to XRF sensors with potential
to upgrade mill feed from 2.5% Zn to approximately 5% Zn with zinc recoveries of 80-85% at low cost
(see Fireweed news release dated July 31 st, 2019). The sorted products of each of the composites will be
returned to Base Metallurgical Laboratories in Kamloops, Canada, where they will be analyzed and the
potential for preconcentration and upgrading will be assessed. If sorting results are favourable, sorting
products will be combined with the fines generated during crushing and then will be subjected to flotation
test work to determine metal recoveries.
The composites from the identical unsorted sample of quarter drill core will be subjected to SMC tests for
comminution, Bond Work Index tests, bulk mineral content analysis , and rougher and cleaner flotation
testing to determine processing characteristics.
Ore Sorting Technology
Sensor-based ore sorting is currently in use at over 50 mining operations across the world 1. A range of
sensors can be used, depending on ore properties. Typically, sensors infer metal abundances on rock pieces
moving on an enclosed conveyor belt unit and high-speed discriminating software distinguishes rocks with
grades above and below a set threshold. At the end of the conveyor belt, focussed high pressure air jets or
mechanical levers separate the designated higher grade rock pieces for processing and reject low-grade and
waste pieces. Sorting therefore increases the metal grade reporting to downstream mineral processing
operations, which is known as preconcentration. XRF is one sensing type that is applied in sensor-based
sorting, for example at AngloAme rican’s Mogalakwena mine in South Africa. The amenability to ore
sorting depends on the material characteristics of the mined rock. The Boundary Zone samples responded
positively to previous XRF testing because zinc values on the surfaces of individual roc k pieces correlate
closely with the overall zinc assays of those rocks and the Boundary Zone mineralization is highly
heterogeneous (see Fireweed news release dated July 31st, 2019).
Boundary Zone Background
Boundary Zone mineralization consists of sphalerite-siderite-pyrite and minor galena in veins, stockworks,
disseminations, and as replacement of matrix and clasts within coarse clastic rocks. Drilling in 2020 at
Boundary Zone West also identified stratiform mineralization similar to the Tom and J ason deposits (see
news release dated November 24th, 2020).
Historical exploration work at Boundary Zone included geochemical and geophysical surveys as well as 24
drill holes that defined a central 200 x 800 m mineralized zone of zinc ( -lead-silver) mineralization within
a broader system over 2 km in strike length. In 2019, Fireweed drilled two holes into Boundary Zone Main.
Both holes intersected wide zones of high -grade replacement -style and vein - and breccia -hosted zinc
mineralization, including 100.0 m (true width) of 8.73% zinc from surface including 6.4 m of 43.53% zinc
within 230.0 m of 4.51% zinc (see Fireweed news releases dated October 16 th, 2019 and November 5 th,
2019). In 2020 Fireweed drilled the discovery holes into the Boundary West Zone (see Fireweed news
release dated 25th February 2021).
Qualified Person Statement
Technical information in this news release has been approved by Jack Milton, P.Geo., Chief Geologist
and a ‘Qualified Person’ as defined under Canadian National Instrument 43-101.
Sampling notes
Drill core was cut into quarters lengthwise with a core saw on site. One quarter core sample was sent for
assay (results reported in Fireweed news releases dated October 16th, 2019 and November 5th, 2019); one
quarter core was taken for metallurgical Sample 1 for ore sorting tests; one quarter core was taken for
metallurgical Sample 2 for unsorted tests; and the last quarter of core was placed back into the core box
for archival purposes. Metallurgical samples 1 and 2 were taken from site to secure storage in Whitehorse,
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Yukon, in 2019. In 2021, metallurgical samples were shipped by transport truck to Base Metallurgical
Laboratories in Kamloops, B.C. for compositing and coarse crushing before forwarding selected
composites by air freight for ore-sorting test work to Steinert’s testing facility in Germany.
About Fireweed Zinc Ltd. (TSXV: FWZ): Fireweed Zinc is a public mineral exploration company
focused on zinc-lead-silver and managed by a veteran team of mining industry professionals. The Company
is advancing its district-scale 940 km2 Macmillan Pass Project in Yukon, Canada, which is host to the 100%
owned Tom and Jason zinc-lead-silver deposits with current Mineral Resources and a PEA economic study
(see Fireweed news releases dated January 10, 2018, and May 23, 2018, respectively, and reports filed on
www.sedar.com for details) as well as the Boundary Zone, Tom North Zone and End Zone which have
significant zinc-lead-silver mineralization drilled but not yet classified as mineral resources. The project
also includes large blocks of adjacent claims (MAC , MC, MP, Jerry, BR, NS, Oro, Sol, Ben, and Stump)
which cover exploration targets in the district where previous and recent work identified zinc, lead and
silver prospects, and geophysical and geochemical anomalies in prospective host geology.
Additional information about Fireweed Zinc and its Macmillan Pass Zinc Project including maps and drill
sections can be found on the Company’s website at www.FireweedZinc.com and at www.sedar.com.
ON BEHALF OF FIREWEED ZINC LTD.
“Brandon Macdonald”
CEO & Director
Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the
policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.
Cautionary Statements
This news release may contain “forward -looking” statements and information relating to the Company and the
Macmillan Pass Project that are based on the beliefs of Company management, as well as assumptions made by and
information currently available to Company management. Such statements reflect the current risks, uncertainties and
assumptions related to certain factors including but not limited to, without limitations, exploration and development
risks, expenditure and financing requirements, general economic conditions, changes in financial markets, the ability
to properly and efficiently staff the Company’s operations, the sufficiency of working capital and funding for
continued operations, title matters, First Nations relations, operating hazards, politi cal and economic factors,
competitive factors, metal prices, relationships with vendors and strategic partners, governmental regulations and
oversight, permitting, seasonality and weather, technological change, industry practices, and one -time events.
Additional risks are set out in the Company’s prospectus dated May 9, 2017, and filed under the Company’s profile
on SEDAR at www.sedar.com. Should any one or more risks or uncertainties materialize or change, or should any
underlying assumptions prove incorrect, actual results and forward-looking statements may vary materially from those
described herein. The Company does not undertake to update forward‐ looking statements or forward‐ looking
information, except as required by law.
1. References for commercial XRF ore sorting operations: https://steinertglobal.com/magnets-sensor-sorting-
units/sensor-sorting/x-ray-sorting-systems/steinert-kss-xf-l/
http://www.radosxrf.com/wp-content/uploads/2015/12/Run-of-Mine-Ore-Sorting-Proof-of-Concept-Plant-
videos-Removed-1-3.pdf