ASX / TSX-V: JRV
OTC: JRVMF / FRA: IHS
HIGHLIGHTS
- Deep drilling, through two exploration holes into the
footwall past the main RAM resource zone, have both intercepted
copper (Cu) and Cobalt (Co) mineralization. These intercepts reside
between 75 to 220 metres outside the current mine wireframe model
underpinning the Idaho Cobalt Operations ("ICO") mine plan.
- The footwall mineralization is considered to be the northern
extension of the Blacktail lode which was historically mined at the
neighbouring Blackbird minesite. The footwall mineralization has
been named Blacktail North.
- Blacktail North confirms the existence of footwall
mineralisation beyond the identified RAM resource at ICO. Jervois
is planning an extensive 2020 field season to explore.
- Due to seasonal constraints and acceleration of feasibility
optimisation, the ICO drilling programme for 2019 has now been
completed. Results are providing valuable sample information for
metallurgical testwork, generation of physical off-take samples for
customers and infill resource drilling.
MELBOURNE, Oct. 15, 2019 /CNW/ - Jervois Mining Limited (the
"Company" or "Jervois") (ASX:JRV) (TSX-V: JRV) (OTC: JRVMF) (FRA:
IHS) is pleased to provide an update on the 2019 drilling programme
at its Idaho Cobalt Operations ("ICO").
Upon completion of the merger with eCobalt Solutions Inc., the
Company mobilized an aggressive drilling programme at ICO in what
remained of the 2019 field season.
Whilst a key purpose of this drilling was to support the
feasibility study ("FS") update, our exploration team wanted to
explore the footwall at the RAM deposit to test a geological model
identified by Jervois through detailed geological structural
modelling. The Company is pleased to advise that the concept has
been successfully validated, with both deep holes drilled into the
footwall of the main RAM resource intercepting copper and cobalt.
This type of mineralistion is analogous to the northern extension
of the Blackbird mine lode known as Blacktail which was
historically mined at the now closed operation adjacent to RAM.
Both deep core holes have intercepted Cu-Co mineralization which
was previously undrilled and unknown. The two holes have been
partially assayed for the Blacktail zone. Further samples from hole
R19-02 are currently at ALS Elko labs in Nevada USA for analysis.
These two intercepts of Blacktail North confirm the exploration
model and demonstrate the potential to add future mineral resources
to the ICO. The deposit is open in all directions and will be
thoroughly drilled in the 2020 field season once drill collar
access has been established.
The results received so far are shown in Figures 1 and 2, Tables
1 and 2.
Table 1: Drillhole Collars
|
Coordinates
|
|
|
|
|
|
BHID
|
UTM_E_NAD83
Z11N
|
UTM_N_NAD83
Z11N
|
|
Elevation
(m)
|
Plan
Dip
|
Plan
Azi
|
Final Depth
(m)
|
R19-01
|
707519.1
|
5002210.6
|
|
2195.1
|
-70
|
245
|
389.5
|
R19-02
|
707546.8
|
5002220.8
|
|
2196.9
|
-75
|
245
|
431.2
|
R19-03
|
707547.1
|
5002223.1
|
|
2196.9
|
-67
|
220
|
164.0
|
R19-04
|
707579.2
|
5002233.8
|
|
2198.2
|
-70
|
245
|
186.8
|
R19-05
|
707579.8
|
5002234.2
|
|
2198.3
|
-75
|
245
|
196.0
|
R19-06
|
707580.5
|
5002234.5
|
|
2198.2
|
-80
|
245
|
232.3
|
R19-07
|
707576.7
|
5002232.7
|
|
|
-65
|
225
|
220.4
|
R19-08
|
707573.0
|
5002276.0
|
|
|
-64
|
252
|
165.2
|
R19-09
|
|
|
-70
|
248
|
177.4
|
R19-10
|
|
|
-76
|
242
|
184.1
|
R19-11
|
707543.0
|
5002261.0
|
|
|
-60
|
250
|
118.6
|
R19-12
|
|
|
-70
|
250
|
127.7
|
R19-13
|
|
|
-62
|
228
|
115.8
|
R19-14
|
707514.0
|
5002291.0
|
|
|
-75
|
227
|
115.5
|
R19-15
|
|
|
-65
|
238
|
116.7
|
R19-16
|
|
|
-68
|
270
|
124.4
|
R19-17
|
707418.9
|
5002243.0
|
|
|
-90
|
0
|
20.7
|
R19-18
|
|
|
-75
|
245
|
16.5
|
R19-19
|
|
|
-55
|
205
|
14.9
|
BHID R19-01 to R19-06
are surveyed. R19-07 to R19-19 are planned to be verified by
survey.
|
Table 2: Significant Drilling Results for Holes R19-01 and
R19-02. Cu>0.3% or Co>0.05% or Au>0.5g/t
BHID
|
Depth
From
(m)
|
Depth
To
(m)
|
Intercept
(m)
|
Cu
(%)
|
Co
(%)
|
Au
(g/t)
|
Composite
|
R19-01
|
170.7
|
171.3
|
0.6
|
0.89
|
0.08
|
0.44
|
1.3m @ 0.62% Cu,
0.05% Co
|
|
171.3
|
172.0
|
0.7
|
0.35
|
0.02
|
0.14
|
|
195.1
|
195.7
|
0.6
|
0.26
|
0.03
|
0.78
|
|
|
299.3
|
299.9
|
0.6
|
0.61
|
0.03
|
0.15
|
|
|
302.4
|
303.0
|
0.6
|
0.47
|
0.05
|
1.10
|
|
|
312.1
|
313.0
|
0.9
|
0.46
|
0.02
|
0.09
|
|
|
313.9
|
314.9
|
0.9
|
0.57
|
0.01
|
0.04
|
2.4m @ 0.81% Cu,
0.07% Co
|
|
314.9
|
315.6
|
0.7
|
0.14
|
0.08
|
0.05
|
|
315.6
|
316.4
|
0.8
|
1.61
|
0.12
|
0.18
|
|
319.4
|
320.6
|
1.2
|
0.43
|
0.01
|
0.03
|
|
|
321.6
|
322.4
|
0.8
|
0.58
|
0.05
|
0.20
|
4.0m @ 0.48% Cu,
0.05% Co
|
|
322.4
|
323.4
|
1.0
|
0.21
|
0.09
|
0.12
|
|
323.4
|
324.0
|
0.6
|
0.76
|
0.03
|
0.11
|
|
324.0
|
324.6
|
0.6
|
0.78
|
0.04
|
0.33
|
|
324.6
|
325.5
|
0.9
|
0.34
|
0.02
|
0.05
|
R19-02
|
200.6
|
201.2
|
0.6
|
0.53
|
0.02
|
0.06
|
|
|
216.7
|
217.3
|
0.6
|
0.24
|
0.10
|
1.29
|
1.5m @ 1.01% Cu,
0.05% Co, 0.63g/t Au
|
|
217.3
|
218.2
|
0.9
|
1.50
|
0.02
|
0.18
|
|
235.0
|
235.8
|
0.8
|
0.33
|
0.03
|
0.05
|
|
|
286.8
|
287.7
|
0.9
|
0.35
|
0.02
|
0.05
|
|
|
308.8
|
309.7
|
0.9
|
0.36
|
0.12
|
0.08
|
|
|
392.6
|
393.4
|
0.8
|
0.39
|
0.00
|
0.05
|
|
Note: Core holes
selectively sampled.
|
Physical drilling has now completed at the ICO, including
drilling for metallurgical testwork and infill resource drilling,
in addition to the exploration holes described above. Logging and
sampling of core continues. Due to the importance of FS
requirements for the other holes, no further exploration was
undertaken of the footwall potential this season. The newly
discovered Blacktail North zone will be tested from locations on
the west side of the mountain to reduce drilling costs in the 2020
field season.
Jervois is excited by these initial developments. The
transaction with eCobalt Solutions Inc. was predicated on the
detailed due diligence of our team and confidence in ICO being
ultimately capable of operating in an environmentally responsible
manner at higher production rates than currently formalised via
existing feasibility studies, and as permitted by the United States
Forest Service. A domestic cobalt refinery within the United States will also be positively
impacted by a mining operation delivering higher volumes of cobalt
concentrate for a longer period.
Quality Assurance
Core samples or geochemical analysis
are sent to ALS Elko Nevada, an independent and fully accredited
laboratory in the USA for analysis
for gold & multi-element Induction Coupled Plasma Spectroscopy.
Core samples from the main Ram zone are sent to SGS Lakefield,
Canada for analysis as per ALS
Elko and for further metallurgical testing. Jervois also has a
regimented Quality Assurance, Quality Control program where at
least 10% duplicates and blanks are inserted into each sample
shipment.
Competent Person's Statement
The information in
this release that relates to Mineral Exploration is based on
information compiled by David Selfe
who is full time employee of the company and a Fellow of the
Australasian Institute of Mining and Metallurgy and Dean Besserer, P.Geol. who is a consultant to
the company and a member of The Association of Professional
Engineers and Geoscientists of Alberta. Both David
Selfe and Dean Besserer have
sufficient experience which is relevant to the style of
mineralization and type of deposit under consideration and to the
activity which they are undertaking to qualify as a Competent
Person as defined in the 2012 Edition of the 'Australasian Code for
Reporting of Exploration Results, Mineral Resources and Ore
Reserves'. David Selfe and
Dean Besserer consent to the
inclusion in the release of the matters based on their information
in the form and context in which it appears.
Disclosure required for TSX-V Regulations
Qualified Person's Statement
The technical content
of this news release has been reviewed and approved by Dean Besserer, P.Geol., the Technical Advisor of
the Company and a Qualified Person as defined by National
Instrument 43-101
Neither TSX Venture Exchange nor its Regulation Services
Provider (as that term is defined in policies of the TSX Venture
Exchange) accepts responsibility for the adequacy or accuracy of
this release.
This news release may contain certain "Forward-Looking
Statements" within the meaning of the United States Private
Securities Litigation Reform Act of 1995 and applicable Canadian
securities laws. When used in this news release, the words
"anticipate", "believe", "estimate", "expect", "target, "plan",
"forecast", "may", "schedule" and other similar words or
expressions identify forward-looking statements or information.
These forward-looking statements or information may relate to
exploration work to be undertaken at ICO, the reliability of third
party information, and certain other factors or information. Such
statements represent the Company's current views with respect to
future events and are necessarily based upon a number of
assumptions and estimates that, while considered reasonable by the
Company, are inherently subject to significant business, economic,
competitive, political and social risks, contingencies and
uncertainties. Many factors, both known and unknown, could cause
results, performance or achievements to be materially different
from the results, performance or achievements that are or may be
expressed or implied by such forward-looking statements. The
Company does not intend, and does not assume any obligation, to
update these forward-looking statements or information to reflect
changes in assumptions or changes in circumstances or any other
events affections such statements and information other than as
required by applicable laws, rules and regulations.
JORC Code, 2012 Edition – Table 1
Section 1 Sampling Techniques and Data
Criteria
|
JORC Code
explanation
|
Commentary
|
Sampling
techniques
|
- Nature and
quality of sampling (eg cut channels, random chips, or specific
specialised industry standard measurement tools appropriate to the
minerals under investigation, such as down hole gamma sondes, or
handheld XRF instruments, etc). These examples should not be taken
as limiting the broad meaning of sampling.
- Include
reference to measures taken to ensure sample representivity and the
appropriate calibration of any measurement tools or systems
used.
- Aspects of the
determination of mineralisation that are Material to the Public
Report.
- In cases where
'industry standard' work has been done this would be relatively
simple (eg 'reverse circulation drilling was used to obtain 1 m
samples from which 3 kg was pulverised to produce a 30 g charge for
fire assay'). In other cases more explanation may be required, such
as where there is coarse gold that has inherent sampling problems.
Unusual commodities or mineralisation types (eg submarine nodules)
may warrant disclosure of detailed information.
|
Sampling is by
diamond drill coring.
All drill core was
sampled contingent on geology and core recovery:
Core was collected
directly from the core barrel into core boxes, and Core samples
were split in half, with the top half of the core analysed and
other half retained as reference core in the tray. Core trays were
clearly labelled with the hole number, tray number and metre
intervals marked.
Samples were cut
along the orientation line before being correctly placed back into
the tray. The half-core was sampled, ensuring that the same side is
consistently sampled, and placed into sample bags labelled with the
assigned sample number. Downhole measurements are recorded using a
Reflex EZ-Trac at 50 foot intervals down each hole and at the end
of every hole.
Field sampling
followed Jervois protocols including industry standard quality
control procedures.
All samples were sent
to ALS Elko Geochemistry, an independent and fully accredited
laboratory in Nevada, USA ("ALS") for analysis for gold and
multi-element Induction Coupled Plasma Spectroscopy ("ICP").
Jervois also has a regimented Quality Assurance, Quality Control
("QA/QC") program where at least 10% standards and blanks are
inserted into each sample shipment.
Sample representivity
is ensured by:
Diamond Core: For all
drilling core was halved for sub‐sampling with a diamond saw. For
PQ, core was then quartered for sampling. Sample intervals range
from 2 feet to 5 feet in length, with majority of samples assayed
over 3 feet intervals.
Handheld XRF
instruments were used to spot check drill core for mineralization,
however those results were not relied on. All sample results
reported on are from ALS Elko Geochemistry.
All of the drilling
was diamond drill core (PQ/HQ). Typically, drill core was sampled
on nominal 3 foot half core samples for HQ and quarter core for
PQ.
All sample analyses
were completed at ALS Elko Geochemistry. and/or SGS Lakefield,
Canada. ALS and SGS are global independent laboratories which are
ISO accredited.
Samples are received
at the laboratory: Bar codes are scanned and logged; samples are
weighed and dried; samples are crushed to 70% less than 2mm, riffle
split off 250g, pulverize split to better than 85% passing 75
microns; all samples are analyzed for 35 elements using ICP-AES and
gold using 30 gram Fire assay for core, both with an AA finish. Any
samples with over-limits specific to base metals or gold are
re-analyzed.
|
Drilling
techniques
|
- Drill type (eg core, reverse circulation,
open-hole hammer, rotary air blast, auger, Bangka, sonic, etc) and
details (eg core diameter, triple or standard tube, depth of
diamond tails, face-sampling bit or other type, whether core is
oriented and if so, by what method, etc).
|
PQ coring was
completed up to the limit of PQ penetration and then reduced to HQ
to the end of hole.
Holes were generally
angled from -55 to -90 degrees at varying azimuths.
|
Drill sample
recovery
|
- Method of
recording and assessing core and chip sample recoveries and results
assessed.
- Measures taken
to maximise sample recovery and ensure representative nature of the
samples.
- Whether a
relationship exists between sample recovery and grade and whether
sample bias may have occurred due to preferential loss/gain of
fine/coarse material.
|
All holes are teched
and all intervals are measured for recovery and RQD's are
calculated. Recovery % recorded in the geotechnical records as
equivalent to the length of core recovered, as a percentage of the
drill run.
Excellent recoveries
were obtained from Diamond drilling.
There is no bias
noted between sample recovery and grade. Excellent recoveries were
obtained from Diamond drilling other than in faulted zones which
were not sampled.
|
Logging
|
- Whether core and
chip samples have been geologically and geotechnically logged to a
level of detail to support appropriate Mineral Resource estimation,
mining studies and metallurgical studies.
- Whether logging
is qualitative or quantitative in nature. Core (or costean,
channel, etc) photography.
- The total length
and percentage of the relevant intersections
logged.
|
Diamond
drilling:
Drill core is
photographed and logged prior to sampling;
Core has been
geologically and geotechnically logged to a level of detail
appropriate to support mineral resource estimation and mining
studies.
Logging has been
conducted both qualitatively and quantitatively; full description
of lithologies, alteration and comments are noted, as well as
percentage estimates on veining and sulphides.
The total length of
all holes was 3117.7m. All depths are listed in the table in the
body of the text. All drill holes are logged in their
entirety.
|
Sub-sampling
techniques and sample preparation
|
- If core, whether
cut or sawn and whether quarter, half or all core
taken.
- If non-core,
whether riffled, tube sampled, rotary split, etc and whether
sampled wet or dry.
- For all sample
types, the nature, quality and appropriateness of the sample
preparation technique.
- Quality control
procedures adopted for all sub-sampling stages to maximise
representivity of samples.
- Measures taken
to ensure that the sampling is representative of the in situ
material collected, including for instance results for field
duplicate/second-half sampling.
- Whether sample
sizes are appropriate to the grain size of the material being
sampled.
|
All core was half-cut
lengthwise using a diamond saw. The HQ core half-core was sampled.
For PQ core half was cut again and quarter core was
sampled.
Samples are received
at the laboratory: Bar codes are scanned and logged; samples are
weighed and dried; samples are crushed to 70% less than 2mm, riffle
split off 250g, pulverize split to better than 85% passing 75
microns; all samples are analyzed for 35 elements using ICP-AES and
gold using 30 gram Fire assay for core, both with an AA finish. Any
samples with over-limits specific to base metals or gold are
re-analyzed.
For core sampling the
same side is consistently sampled, half-core is retained in the
tray for HQ for PQ quarter core is retained and half core is
reserved for metallurgical test sample. The assay sub- sample is
placed into sample bags labelled with the assigned sample
number.
One in 20 samples is
duplicated where the core is quartered and a quarter cut sample is
analysed as a duplicate. The remaining quarter samples is retained
in the tray.
Sample sizes of 2-3
kg are appropriate for the grain size of material. The sample
preparation technique and sample sizes are considered appropriate
to the material being sampled.
|
Quality of assay
data and laboratory tests
|
- The nature,
quality and appropriateness of the assaying and laboratory
procedures used and whether the technique is considered partial or
total.
- For geophysical
tools, spectrometers, handheld XRF instruments, etc, the parameters
used in determining the analysis including instrument make and
model, reading times, calibrations factors applied and their
derivation, etc.
- Nature of
quality control procedures adopted (eg standards, blanks,
duplicates, external laboratory checks) and whether acceptable
levels of accuracy (ie lack of bias) and precision have been
established.
|
The ICP-AES and Fire
Assay (30 gram) are considered total and are high
quality.
Jervois has a
regimented Quality Control protocol which has consisted of
systematic submission of blanks, standards and duplicates in
addition to those conducted at the laboratory.
Precision levels for
all blanks, standards and duplicate samples fell within acceptable
ranges.
|
Verification of
sampling and assaying
|
- The verification
of significant intersections by either independent or alternative
company personnel.
- The use of
twinned holes.
- Documentation of
primary data, data entry procedures, data verification, data
storage (physical and electronic) protocols.
- Discuss any
adjustment to assay data.
|
Significant
intersections are alternatively verified by the CP and QP of the
company.
No holes have been
twinned in this drill programme.
Data is collected
using a customized template on MS Excel. The data is backed up
systematically on and off site as well as on the cloud. As well,
data is recorded using a master Microsoft Office Excel
spreadsheet.
All data below
detection limit have been entered as zero.
Samples received
damaged at the laboratory, or with insufficient sample weight for
analysis had the interval or location left blank.
|
Location of data
points
|
- Accuracy and
quality of surveys used to locate drill holes (collar and down-hole
surveys), trenches, mine workings and other locations used in
Mineral Resource estimation.
- Specification of
the grid system used.
- Quality and
adequacy of topographic control.
|
All collars were
surveyed by hand held Garmin GPS. Not all collars have been
surveyed but will be at completion of the drilling programme by
trained surveyors. Down-hole surveys were routinely carried out on
all holes using a Reflex EZ-Trac at 50 foot intervals downhole.
Holes were setup on collar using a Reflex TN14 Gyro.
All datum is
collected and recorded in UTM_NAD83 Z11N
The 3D location of
the individual samples is considered to be adequately established,
consistent with accepted industry standards.
|
Data spacing and
distribution
|
- Data spacing for
reporting of Exploration Results.
- Whether the data
spacing and distribution is sufficient to establish the degree of
geological and grade continuity appropriate for the Mineral
Resource and Ore Reserve estimation procedure(s) and
classifications applied.
- Whether sample
compositing has been applied.
|
To date, due to the
exploratory nature of the footwall drilling, the spacing is wide.
Assay results for only one hole and for only the footwall intercept
have been received. Further intervals have been sampled but the
assays are not yet available.
The intervals reported for these 2 holes is exploratory and data
spacing would not be considered sufficient to establish a Mineral
Resource or Ore Reserve Estimation for this particular
mineralisation intercept.
Data is reported both
composited and uncomposited.
|
Orientation of
data in relation to geological structure
|
- Whether the
orientation of sampling achieves unbiased sampling of possible
structures and the extent to which this is known, considering the
deposit type.
- If the
relationship between the drilling orientation and the orientation
of key mineralised structures is considered to have introduced a
sampling bias, this should be assessed and reported if
material.
|
Drilling sections are
orientated perpendicular to the strike of the host
rocks.
Drill holes were
inclined between 55° and 90° to optimize intercepts of
mineralisation with respect to thickness and
distribution.
Drilling with angled
holes in most instances provides a representative sample across the
stratigraphy.
|
Sample
security
|
- The measures taken to ensure sample
security.
|
All individual
samples are bagged and sealed with a zip tie. Then individual
samples are bagged in poly woven sacks and sealed with a zip tie.
The samples are sent by courier to the lab and tracked. To date, no
sample shipments have had reported problems and/or a breach in
security.
|
Audits or
reviews
|
- The results of
any audits or reviews of sampling techniques and
data.
|
Jervois protocols
consist of a regimented internal QA/QC which match or exceed global
industry standards. This drilling program has not been subjected to
audits or reviews so far, however this will be completed as part of
the current feasibility study of which this drilling is a
part.
|
Section 2 Reporting of Exploration Results
Criteria
|
JORC Code
explanation
|
Commentary
|
Mineral tenement
and land tenure status
|
- Type, reference
name/number, location and ownership including agreements or
material issues with third parties such as joint ventures,
partnerships, overriding royalties, native title interests,
historical sites, wilderness or national park and environmental
settings.
- The security of
the tenure held at the time of reporting along with any known
impediments to obtaining a licence to operate in the
area.
|
Idaho Cobalt
Operations consists of 243 unpatented mineral claims totalling 5990
acres. The claims are 100% owned by Jervois subsidiary Formation
Capital LLC and are in good standing.
Unpatented Mineral
Claims:
Ownership of
unpatented mining claims in the U.S. is in the name of the holder,
with ownership of the minerals belonging to the United States of
America, under the administration of the U.S. Bureau of Land
Management. Under the Mining Law of 1872, which governs the
location of unpatented mining claims on federal lands, the locator
has the right to explore, develop and mine minerals on unpatented
mining claims without payments of production royalties to the
federal government.
Annual claim
maintenance and filing fees paid before September 1st
each year are the only federal encumbrances to unpatented mining
claims. Exploration plans are permitted and administered by the
Unites States Forestry Service.
The United States
Department of Agriculture Salmon Challis National Forest (the
Forest Service) issued a revised Record of Decision (the ROD) for
the ICO in January 2009. The ROD described the decision to approve
a Mine Plan of Operations (MPO) for mining, milling and
concentrating mineralized material from the ICO. The ROD was
subsequently affirmed by the Forest Service in April 2009. The Plan
of Operations at the ICO mine and mill remained unchanged and the
ROD remains in place. In December 2009, the Forest Service approved
the MPO allowing for the commencement of ICO
construction.
There are no known
encumbrances.
|
Exploration done
by other parties
|
- Acknowledgment and appraisal of exploration by
other parties.
|
The ICO came under
Jervois management following the merger with eCobalt in 2019. Prior
to this merger, the area has a long history of copper and cobalt
exploration and mining. Copper mineralization in the Blackbird
Creek area was discovered in 1892, and the area was soon explored
as both a copper and gold prospect. The area was first mined by
Union Carbide at the Haynes-Stellite Mine located south of the
present ICO claim block, during World War I. Union Carbide mined
approximately 4,000 tons of cobalt-bearing ore before ceasing
operations. From 1938 to 1941, the Uncle Sam Mining and Milling
Company operated a mine at the south end of the present Blackbird
mine and reportedly mined about 3,600 tons of ore.
Calera Mining
Company, a division of Howe Sound Company, developed and mined the
Blackbird deposit between 1943 and 1959 under a contract to supply
cobalt to the U.S. government. Calera stopped mining when the
government contract was terminated in 1960.
Machinery Center Inc.
mined from the district between 1963 and 1966, when Idaho Mining
Company (owned by Hanna Mining Company) purchased the property.
Noranda optioned the property from Hanna in 1977 and carried out
extensive exploration, mine rehabilitation and metallurgical
testing. In 1979 Noranda and Hanna formed the Blackbird Mining
Company (BMC) to develop the property. BMC completed an internal
feasibility study of their property at the time, including material
from the Sunshine deposit in 1982. BMC allowed perimeter claims to
lapse in 1994, and eCobalt restaked much of that ground. From 1995
to the present, eCobalt completed surface geochemical sampling and
drilled 158 diamond drill holes on the ICO ground.
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Geology
|
- Deposit type, geological setting and style of
mineralisation.
|
Deposit
Types:
Whilst the deposits
in the Idaho Cobalt Belt have been studied over many years the
deposit types are still a subject of debate. Prior to 2005 the
overriding opinion was that the deposits are sedimentary exhalative
and are referred to as the Blackbird Sediment Hosted Cu-Co. And
have been described as stratabound iron-, cobalt-, copper-, and
arsenic-rich sulphide mineral accumulations in nearly
carbonate-free argillite/siltite couplets and quartzites
Post 2005 the
discovery of high concentrations of rare earth elements (REE) lead
to the postulation that the deposits are not volcanogenic massive
sulphide or sedimentary exhalative deposits but instead are iron
oxide-copper-gold (IOCG) deposits
Geological
Setting:
The ICO is situated
in the Idaho Cobalt Belt, a 30- to 35-mile long metallogenic
district characterized by stratiform/tabular copper-cobalt
deposits. The deposits are hosted by a thick, dominantly clastic
sequence of Middle Proterozoic age sandwiched between late
Proterozoic quartz monzonitic intrusions. The clastic sediments
were deposited in a large fault-bounded basin, probably as large
submarine fan complexes and/or deltaic aprons that were frequently
"drowned" by continuing subsidence within the basin. All
significant copper-cobalt deposits and occurrences are found in the
Proterozoic Apple Creek Formation, which constitutes the base of
this sequence. This formation was originally correlated with
Pritchard Formation metasediments of the Belt supergroup to the
north, its age being constrained by dates of 1.37 Ga for
adamellites intruding the sequence and 1.7 Ga from mafic dykes and
sills emplaced along the basin margin faults.
The structure of the
Apple Creek Formation is dominated by the regional rift structure.
Cobalt-copper-gold mineralization occurs along a
northwest-southeast trending structure parallel to and west of the
central axis of the rift.
There is a series of
northerly trending faults that are considered to represent initial
growth faults, reactivated by Laramide and younger events. The
district has also been affected by north-easterly structures of the
Trans-Challis Fault Zone.
The ICO is hosted in
Proterozoic age meta-sediments found on the east side of the
central Idaho Batholith comprising granitic-to-granodioritic rocks.
The Idaho Cobalt Belt represents a distinct district dominated by
stratabound cobalt + copper ± gold mineralization, with a
remobilized constituent. The district is underlain by strata of the
middle Proterozoic-age Apple Creek Formation, which is an
upward-thickening, upward-coarsening clastic sequence at least
49,000 feet thick that represents a major basin-filling episode and
was formerly considered part of the Yellow Jacket
Formation.
The Apple Creek can
be divided into three units. The lower unit of the Apple Creek
Formation is over 15,000 feet thick and consists mainly of
argillite and siltite, with lesser occurrences of fine-grained
quartzite and carbonates. Graded bedding and planar to wavy laminae
are common in the lower unit, which is locally metamorphosed to
phyllite. The middle unit of the Apple Creek Formation is up to
3,600 feet thick and comprises several upward-coarsening sequences
of argillite, siltite, and quartzite, with distinctive biotite-rich
interbeds that generally have a direct correlation to
mineralization. The middle unit hosts the majority of the known
cobalt, copper and gold occurrences in the Idaho Cobalt Belt. The
upper unit exceeds 9,800 feet in thickness and is predominantly
composed of thin- to thick bedded, very fine- to fine-grained
quartzite.
Mafic tuffs within
the Apple Creek Formation are the oldest igneous rocks exposed in
the Sunshine-Blackpine district. They are accompanied by felsic
tuffs and carbonatitic tuffs. Some mafic dikes and sills intrude
the Apple Creek Formation and may be comagmatic with the mafic tuff
beds. Several small lamproitic diatremes may also be coeval with
mafic volcanism.
The Apple Creek
Formation has undergone varying degrees of regional metamorphism,
ranging from greenschist facies in the southern part of the
district to amphibolite grade facies in the northern part of the
district. Several types of mafic dikes and sills, ranging from 3
ft. to 100 ft. thick, intrude the Apple Creek Formation and are
interpreted as feeders to the exhalative mafic tuffs, which are
most abundant in areas of intrusive actvity
Style of
Mineralization:
Mineralization at the
ICO is characterized as syngenetic, stratiform/tabular exhalative
deposits within, or closely associated with, the mafic sequences of
the Apple Creek Formation. This mineralization is dominantly
bedding concordant and the deposits range from nearly massive to
disseminated. Some crosscutting mineralization is present that may
be in feeder zones to the stratiform mineralization or may be due
to remobilization locally into fracture quartz veins and/or
crosscutting structures.
Dominant minerals
include cobaltite (CoAsS) and chalcopyrite (CuFeS2), with lesser,
variable occurrences of gold. Other minerals present in small
quantities are pyrite (FeS2), pyrrhotite (FeS), arsenopyrite
(FeAsS), linnaeite ((Co Ni)3S4), loellingite (FeAs2), safflorite
(CoFeAs2), enargite (Cu3AsS4) and marcasite (FeS2).
Recently, rare-earth
minerals have been identified in samples from the deposit as
monazite, xenotime and allanite. At this time, these minerals have
not been considered for potential recovery as by-products of the
Co-(Cu-Au).
The Ram is the
largest and best-known deposit in the ICO area. It consists of a
Hanging-wall Zone with 3 primary and 4 minor horizons, a Main Zone
comprising 3 horizons, and a Footwall Zone with 3 horizons. These
sub-parallel horizons generally strike N15oW and dip 50o – 60o to
the northeast. Most of the significant Co mineralization is
associated with exhalative lithologies i.e. biotitic tuffaceous
exhalate (BTE), siliceous tuffaceous exhalate (STE), and quartzite
with impregnations of biotitic tuffaceous exhalate (QTZ/BTE) or
siliceous tuffaceous exhalate (QTZ/STE).
|
Drill hole
Information
|
- A summary of all
information material to the understanding of the exploration
results including a tabulation of the following information for all
Material drill holes:
-
- easting and
northing of the drill hole collar
- elevation or RL
(Reduced Level – elevation above sea level in metres) of the drill
hole collar
- dip and azimuth
of the hole
- down hole length
and interception depth
- hole length.
- If the exclusion
of this information is justified on the basis that the information
is not Material and this exclusion does not detract from the
understanding of the report, the Competent Person should clearly
explain why this is the case.
|
All Material drill
holes relating to this report are detailed in the table included in
the body text of the report.
|
Data aggregation
methods
|
- In reporting
Exploration Results, weighting averaging techniques, maximum and/or
minimum grade truncations (eg cutting of high grades) and cut-off
grades are usually Material and should be stated.
- Where aggregate
intercepts incorporate short lengths of high grade results and
longer lengths of low grade results, the procedure used for such
aggregation should be stated and some typical examples of such
aggregations should be shown in detail.
- The assumptions
used for any reporting of metal equivalent values should be clearly
stated.
|
For this report
weighted averaging has been used in reported composit invervals and
individual results are also listed, no grade truncations etc. has
been used.
Aggregate intercepts
are reported using a grade metre calculation. For example: ((assay
x meter interval sampled)+ (assay x meter interval sampled)+ (assay
x meter interval sampled) / divided by total number of meters in
the interval). Individual sample intercepts are also
shown.
No metal equivalent
values have been reported.
|
Relationship
between mineralisation widths and intercept lengths
|
- These
relationships are particularly important in the reporting of
Exploration Results.
- If the geometry
of the mineralisation with respect to the drill hole angle is
known, its nature should be reported.
- If it is not
known and only the down hole lengths are reported, there should be
a clear statement to this effect (eg 'down hole length, true width
not known').
|
As the exact
orientation of the Blacktail North mineralisation is not known, the
geometry of the mineralisation with respect to the drill hole angle
is not precisley know but is assumed to be similar to, if not
parallel to that of the known Ram deposit.
Not withstanding
that, true width is not known and only down hole length is
reported.
|
Diagrams
|
- Appropriate maps and sections (with scales) and
tabulations of intercepts should be included for any significant
discovery being reported These should include, but not be limited
to a plan view of drill hole collar locations and appropriate
sectional views.
|
Plan and cross
section included in the body of the report.
|
Balanced
reporting
|
- Where comprehensive reporting of all Exploration
Results is not practicable, representative reporting of both low
and high grades and/or widths should be practiced to avoid
misleading reporting of Exploration Results.
|
Assay returns are
incomplete. The primary exploration target in the footwall of the
known Ram deposit has been intercepted and reported in this
release. The drilling programme is completed but assaying is
ongoing.
|
Other substantive
exploration data
|
- Other exploration data, if meaningful and
material, should be reported including (but not limited to):
geological observations; geophysical survey results; geochemical
survey results; bulk samples – size and method of treatment;
metallurgical test results; bulk density, groundwater, geotechnical
and rock characteristics; potential deleterious or contaminating
substances.
|
Table 1 summarizes
other exploration data. It includes: ground geophysics (magnetics,
VLF TEM); geochemical surveys (soil sampling); rock grab sampling;
and trenching.
|
Further
work
|
- The nature and
scale of planned further work (eg tests for lateral extensions or
depth extensions or large-scale step-out drilling).
- Diagrams clearly
highlighting the areas of possible extensions, including the main
geological interpretations and future drilling areas, provided this
information is not commercially sensitive.
|
Assays are in train at
ALS Elko for the remainder of the 2 holes reported here. Further
infill drilling on the Ram deposit is ongoing.
Planning for further
surface exploation drilling will commence when all assay data for
the holes has been received.
|
TABLE 1 – OTHER EXPLORATION DATA
Data
Type
|
Summary of
Results
|
Airborne
Geophysics
|
Not
Applicable
|
Ground
Geophysics
|
A VLF-EM and Ground
Magnetics survey was completed in 1996 over the ICO claims. The
results were weak and inconclusive. No follow-up work was
recommended.
|
Geochemical
Surveys
|
In 1995, soil
sampling of selected areas was conducted on lines spaced 200 ft.
and 400 ft. apart, with samples collected at intervals of 100 ft.
along the lines.
In 1996, the soil
grid was extended north and soil samples were collected on lines
spaced 200 ft. apart with samples collected at 25 ft. intervals
along the lines. Some infill samples were collected from the 1995
soil grid. Other parts of the grid were also extended and sampled
on 25 ft. intervals where it was deemed warranted.
A total of 8,427 soil
samples were collected during the 1995/1996 campaign. A further 95
soil samples were taken in 1997.
Other exploration
activities conducted during 1995/1996 include surface geological
mapping at a scale of 1 in. to 100 ft.
|
Trenching
|
In 1995/1996 mapping
of old trenches and prospect pits, and collection of 979 surface
rock samples including those from trenches. In 1997 three trenches,
623 ft. long in aggregate, were excavated within the "prism" of the
road; the trenches were mapped and 83 rock samples were
collected.
|
Geochemical Survey
Results
|
The 1995 soil
sampling program lead to the discovery of the southern end of the
Ram target.
|
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SOURCE Jervois Mining Limited