Maiden JORC Resource Statement for Blue Rock Go...
African Consolidated Resources plc / Ticker: AFCR / Index: AIM / Sector: Mining
22 July 2010
African Consolidated Resources plc ('ACR' or 'the Company')
Maiden JORC Resource Statement for Blue Rock Gold Project
African Consolidated Resources plc, the AIM listed resource development company
focussed in Zimbabwe, is pleased to announce that it has achieved the 1 million
ounce JORC compliant gold resource milestone following the publication of a
maiden JORC Resource at the Blue Rock gold project ('Blue Rock'), located in the
Gadzema greenstone belt near Chegutu, 100km southwest of Harare.
Highlights
* Maiden JORC Resource at Blue Rock totals 8.5 million tonnes @ 1 g/t for
270,000 oz, using a cutoff grade of 0.6 g/t
* ACR's total JORC compliant gold resources at its Pickstone-Peerless, Giant
and Blue Rock projects now 1,085,000 ounces
* Assay results awaited for diamond drilling quality control holes. Â Once
quality control checks are complete it is hoped that a significant
proportion of the maiden Resource can be re-classified in the Indicated
category
* Maiden Resource based on drilling to May with 20 RC holes completed since
identifying new trend, 250m from the Blue Rock trend
ACR Chief Executive Officer Andrew Cranswick said, "This maiden resource from
our Blue Rock gold project adds further tangible value to our growing portfolio
of gold projects in the northern midland greenstone belts in Zimbabwe, where our
JORC compliant resources now exceed 1 million ounces. Â This latest resource
again reiterates the considerable potential of this highly prospective area,
which we intend to crystallise through additional exploration and development.
"Importantly, this resource statement, which exceeds management expectations,
highlights the attractive modelling of the Blue Rock orebody. Â Gold
mineralisation extends to near surface, demonstrating that it is well suited for
open pit mining which underpins the potential for robust economics from this
target. Â Our work programme will now focus on the delineation of mineralisation
along the 5km of strike between Blue Rock and the Giant Mine, with drill
intersections to date demonstrating similar broad zones of silica-pyrite
alteration and gold mineralisation. When viewed alongside the BFS roadmap ACR
has recently outlined in its partnership MOU's, the on-going delineation of
resources fits the strategy of extracting value from our assets through
large-scale gold production".
The Blue Rock Resource covers 500m of strike of ultramafic schists interbedded
with banded iron formations and minor mafic volcanics. Â Later felsic intrusions
are emplaced along extensive NNE structures, and have been extensively altered
by silica-pyrite mineralisation. Â Gold mineralisation occurs within banded
iron-formations (where it was historically mined), in narrow quartz veins and in
broad zones in the felsic intrusives. Minor mineralisation extends into the
ultramafic schists.
A JORC Inferred Resource has been calculated by Hellman and Schofield ('H&S')
consultants of Perth, Western Australia as 8.5 million tonnes @ 1 g/t for
272,000 oz, using a cutoff grade of 0.6 g/t. Â This result is above management's
expectations, partly due to the generally broad and consistent gold intercepts
(up to 30m), which generate a coherent and robust block model. Â The modelling
generates high tonnes per vertical metre, well suited to open pit mining. Â The
orebodies extend to near surface (below shallow soil cover), and there appears
to be a moderate supergene enrichment in the oxide zone (approx 0 to 30m) which
generates attractive mining targets at very shallow depths.
ACR's total gold inventory is summarised in Table 1 below:
+--------------------------+---------+-----+----------+------+-----------------+
|Table 1: ACR Â Resources | Â | Â | Â | Â | Â |
|July 2010 | | | | | |
+--------------------------+---------+-----+----------+------+-----------------+
|Â | Oz |Grade| Tonnes |Cutoff| JORC Category |
| | | | | g/t | |
+--------------------------+---------+-----+----------+------+-----------------+
|Peerless ACR drilling | 210,000| 1.4| 4,600,000| 0.5|Inferred |
+--------------------------+---------+-----+----------+------+-----------------+
|Concession ACR drilling | 240,000| 1.5| 4,800,000| 0.5|Inferred |
+--------------------------+---------+-----+----------+------+-----------------+
|Dumps, Pickstone-Peerless | Â | Â | Â | Â |Â |
+--------------------------+---------+-----+----------+------+-----------------+
| Big Red| 15,900| 1.3| 380,000| 1.0|Measured |
+--------------------------+---------+-----+----------+------+-----------------+
| Football Field| 18,800| 1.0| 586,000| 1.0|Measured |
+--------------------------+---------+-----+----------+------+-----------------+
| Concentrate| 28,300| 4.4| 200,000| 1.0|Measured |
+--------------------------+---------+-----+----------+------+-----------------+
|Total Pickstone-Peerless | 513,000| 1.5|10,566,000| Â |Â |
|Resource | | | | | |
+--------------------------+---------+-----+----------+------+-----------------+
| Â | Â | Â | Â | Â |Â |
+--------------------------+---------+-----+----------+------+-----------------+
|Giant Resource[1] | 300,000| 2.2| 4,400,000| 1.0|Inferred |
+--------------------------+---------+-----+----------+------+-----------------+
|Blue Rock Resource | 272,000| 1.0| 8,500,000| 0.6|Inferred |
+--------------------------+---------+-----+----------+------+-----------------+
|TOTAL ALL |1,085,000| 1.5|23,466,000| Â |Inferred, |
| | | | | |measured |
+--------------------------+---------+-----+----------+------+-----------------+
|[1]Excludes Giant Dump - | Â | Â | Â | Â | Â |
|to be JORC calculated | | | | | |
+--------------------------+---------+-----+----------+------+-----------------+
|Â | Â | Â | Â | Â | Â |
+--------------------------+---------+-----+----------+------+-----------------+
The Blue Rock Resource is based on 73 Reverse Circulation (RC) holes totalling
9,158m on 13 lines spaced 40m apart. Drill spacing along lines is generally
30-40m. Â Drillholes were angled 60 degrees west at approximate right angles to
the north-trending orebody. Â The orebody dips steeply east at 70-80 degrees,
hence drill intercepts are close to true thickness. Â Maximum drillhole length
was 180m, allowing the orebody to be modeled to a maximum vertical depth below
surface of 200m. ACR have undertaken bulk density determinations of 116 core
samples originating from two diamond core holes (BRDD0001 and BRDD002). Figure
3 shows a plan projection of the drilling.
In addition to the RC drilling, four diamond drill holes ('DDH') have been
completed for quality control purposes, to twin the RC drilling and cross-check
RC grades, particularly below the water table which stands at about 30m below
surface. Â Diamond core assays are awaited. Visually, the diamond core
intersected broad zones of mineralisation similar to that logged in the RC
holes; however until quality control checks are complete, ACR and H&S regard it
prudent to classify the Resource as Inferred. Once quality control checks are
complete it is hoped that a significant proportion of the maiden Resource can be
re-classified in the Indicated category.
Significant drill intersections making up this Resource have been previously
reported in the May 2010 Technical Update, which is available for download on
our website at www.acrplc.com. Â The H&S JORC document will also be available for
download from the same website following the publication of this announcement.
Figure 1: Â Blue Rock Project Area - Geological Map and Drillhole Locations
Ongoing Exploration
The Blue Rock project is one of several targets in the Gadzema greenstone belt
that is being actively explored this year. Â Since 2006, ACR has completed over
27,000m of RC drilling at the Giant Mine, Blue Rock and Shlegani projects,
within a semi-contiguous land holding covering over 10km of strike length of the
Gadzema belt. Â Joint venture negotiations are underway with neighbouring
landholders to consolidate the land position.
ACR now has a good understanding of the regional geology and ore controls at
Blue Rock, and believes additional, similar bodies will be discovered in the
5km of strike between Blue Rock and the Giant Mine to the north. Additional
drilling of 20 RC holes to the north-east of Blue Rock has identified another
trend (Berks trend) parallel to, and 250m to the east of the Blue Rock trend
(see drillhole locations, Figure 2.). The Berks trend is being drill tested over
a strike length of over 600m. Initial results returned from the lab are positive
with 3g/t-intercepts close to surface.
The Berks trend together with the Shlegani prospect (3 km north of Blue Rock,
see Figure 2), previously drilled by ACR, will be the focus of ongoing
exploration at Gadzema, where over 5,000m of RC drilling is budgeted in the
coming months.
Figure 2: Â Gadzema belt - Location of ACR RC drilling to date on aeromagnetic
image.
Technical Details
H&S was commissioned by ACR to estimate the Mineral Resources at the Blue Rock
gold project in Zimbabwe.
Information supplied for the current study includes sample and assay data for
73 RC drill holes and four DDH drilled by ACR. Â At the time of compiling the
resource estimate for Blue Rock the sample and assay information relating to the
DDH's were not available. Â H&S recommend that the Blue Rock resource estimate be
updated once the DDH sample information has been received by ACR.
Recoverable resources have been estimated using the method of Multiple Indicator
Kriging (MIK) with block support adjustment. Â The model estimates resources into
panels with dimensions of 20mE by 20mN by 5mRL. Â MIK of gold grades used
indicator variography based on the resource sample grades, with continuity of
gold grades characterised by indicator variograms at 14 indicator thresholds. Â A
block support adjustment, incorporating an adjustment for Information Effect,
was used to estimate the recoverable gold resources assuming a selective mining
unit of 4mE by 8mN by 2.5mRL and grade control sampling at 6mE by 8mN by
1.5mRL. Â The shape of the local block (smallest mining unit) gold grade
distribution has been assumed lognormal within each panel.
The recoverable resource estimates within each panel have been modelled
according to the distribution of sampling in the kriging neighbourhood, through
three progressively less stringent search and sample criteria, producing three
categories of resource panels. This classification scheme takes into account the
uncertainty in the estimates related to the proximity and distribution of the
informing composites.
The Blue Rock resource estimates are reported below at a series of cut-off
grades, which span the range of interest for open pit mine optimisation and mine
planning. Â The estimates are constrained by the natural surface as estimated
from drill hole collars. Â The estimates are considered recoverable by mining and
H&S do not recommend application of ore loss and dilution factors in quantifying
ore reserves. Â The figures in this table are rounded to reflect the precision of
estimates and may exhibit rounding errors.
+------------------------------------------+
| Â Mineral Resource Estimate for Blue Rock |
| |
| Inferred |
| |
| cut-off Tonnes Grade Ounces |
| |
| Mt g/t Au K oz |
| |
| 0.40 13.9 0.8 359 |
| |
| 0.50 10.9 0.9 316 |
| |
| 0.60 8.5 1.0 272 |
| |
| 0.70 6.5 1.1 230 |
| |
| 0.80 4.9 1.2 193 |
| |
| 0.90 3.7 1.3 161 |
| |
| 1.00 2.9 1.5 135 |
| |
| 1.10 2.2 1.6 113 |
| |
| 1.20 1.8 1.7 95 |
+------------------------------------------+
Figure 3: Drill hole collars and hole traces.
Gold intercepts displayed as histograms
Figure 4 to Figure 7 show a series of cross-sections through the resource data,
domain interpretations and MIK model. Â The plot show MIK panels coloured by
estimated mean grades (e-type estimates) and the east dimension of the panels
scaled by the recoverable proportions above 0.5g/t Au cut-off. Â The model domain
boundaries are shown as polygons (red = Domain 1 and magenta = Domain 2) and the
interpretations of topography (green), base of highly weathered (brown) and top
of fresh (blue) are shown as lines, the latter two used to define the
sub-domains in the MIK model.
Figure 4: Cross Section 7,999,400mN through resource model and drill holes
Figure 5: Cross Section 7,999,320mN through resource model and drill holes
Figure 6: Cross Section 7,999,200mN through resource model and drill holes
Figure 7: Cross Section 7,999,120mN through resource model and drill holes
The work reported herein was undertaken by Nic Johnson who is a full-time
employee of H&S and a Member of the Australian Institute of Geoscientists. Â Mr.
Johnson has sufficient experience which is relevant to the style of
mineralisation and type of deposit under consideration to qualify as a Competent
Person in terms of JORC standards for reporting of mineral resources. Â Mr.
Johnson has not visited the Blue Rock gold project.
H&S accepts responsibility for classifying the current estimates as Inferred,
providing ACR nominate a Competent Person, or Persons to accept responsibility
for the sampling data and bulk densities applied to the estimate and to attest
to the reasonable prospect of eventual economic extraction of the mineral
resources. Â The Competent Person for ACR is Michael Kellow, Technical Director,
who has sufficient experience which is relevant to the style of mineralisation
and type of deposit under consideration to qualify as a Competent Person in
terms of JORC standards for reporting of mineral resources. Mr Kellow meets the
definition of a "qualified person" as defined in the AIM Note for Mining, Oil
and Gas Companies.
**ENDS**
For further information visit www.acrplc.com or please contact:
Andrew Cranswick African Consolidated Resources plc +44 7920 189010
Roy Tucker African Consolidated Resources plc +44 1622 816918
+44 7920 189012
Richard Greenfield Ambrian Partners Limited +44 20 7634 4700
Hugo de Salis St Brides Media & Finance Ltd +44 (0) 20 7236 1177
Susie Callear St Brides Media & Finance Ltd +44 (0) 20 7236 1177
Glossary of Technical Terms
Term/ Acronym Explanation
aeromagnetics magnetic survey carried out with a sensor in
an aircraft;
archaean rocks greater than 2,600 Ma in age;
argillaceous a sedimentary rock dominated by clay and
silt-sized particles;
Au chemical symbol for gold;
concentrate normally of metallic minerals such as pyrite
and arsenopyrite after removal of gangue;
Cu chemical symbol for copper;
DDH diamond drill hole
diamond drilling drilling method using a diamond-impregnated
cutting bit to obtain a core sample of rock;
electromagnetic survey geophysical technique using electrical
currents to detect conductive bodies below
surface.  Conductive  bodies include
 massive-sulphides that may contain base
metals;
EM survey see electromagnetic survey;
fault a fracture or break  within a body  of rock
across  which some  movement  has occurred;
felsic intrusive an  igneous rock   of   granitic
composition  that  is intruded  into
surrounding strata;
fold  geological term for a curve or bend of planar
surfaces in rocks;
geophysics mineral prospecting  systems  designed to
 detect mineralisation  using  the physical
properties of rocks;
igneous rock originally molten can  be volcanic  or
intrusive
IP survey "Induced Potential"  -  a  geophysical
technique  to  detect  disseminated
sulphide mineralization;
JORC Joint Ore  Reserves Committee  of  the
Australasian Institute  of Mining  and
Metallurgy;
kriging A geostatistical procedure used for estimating
ore reserves.
lodes a discrete, rich portion of an orebody that
has   a   distinct   spatial orientation,
often controlled by faults and folds
mafic rock An intrusive or extrusive volcanic rock rich
in dark-coloured minerals rich in magnesium
and iron. Â Basalt and gabbro are common types.
magnetic survey measurements of  the  perturbation  in the
earth's magnetic  field caused  by magnetic
minerals in rocks;
mineralisation metallic minerals such as gold, base metals,
pyrite and arsenopyrite incorporated in rocks;
Mineralised zones     hydrothermally  altered   structural
features   containing   potentially
valuable minerals;
orebody economically  viable  portion  of  a
mineralised zone;
pyroxenite an ultrabasic rock rich in pyroxene  - a
silicate mineral;
quartz silicon oxide mineral  very common  in
hydrothermal deposits;
radiometrics  the  measurement  by  spectrometer  of
radiation  energy  given  off   by
radioactive rock-forming minerals, usually
Uranium, Thorium, Potassium;
resource mineral resource  as  defined  by  the JORC
Code 2004;
reverse circulation (RC) drilling rotary percussion drilling whereby the RC
sample is  returned from  the  cutting head
inside the rod string to  surface thereby
 avoiding  contamination from the walls of the
hole;
rotary air blast (RAB) drilling Open-hole  drilling  whereby  drill RAB
cuttings are  returned to  surface  by
compressed air  in an  un-lined  hole;
contamination  is  possible  from  the walls
of the hole;
schist metamorphic rock  with well  developed
foliation;
shear zone zone of multiple fractures or discontinuities
in rock, either ductile or brittle;
siltstone fine grained usually quartz rich sedimentary
rock; where calcareous contains calcium or
magnesium carbonate;
stockworks zone of multiple quartz filled fractures with
individual veins often of random orientation;
strike the horizontal orientation of a planar
geological feature;
sulphide  sulphur bearing metallic mineral;
supergene near-surface weathering processes often
leading to enrichment of gold, copper etc from
fluctuations of the water table and oxidation
chemistry.
thrust shallow dipping fault where the upper body of
rock overrides the lower portion;
Ultramafic (ultrabasic) Igneous rocks with a low silica content and
high magnesium content  (generally >18% MgO),
high FeO, and  usually comprises >90% mafic
minerals
[HUG#1433331]
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(i) the releases contained herein are protected by copyright and
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originality of the information contained therein.
Source: African Consolidated Resources Plc via Thomson Reuters ONE
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