JORC resource for the Maximus target at Arapua

RNS Number : 1782F
Harvest Minerals Limited
26 July 2016
 

26 July 2016

 

Harvest Minerals Limited

("Harvest" or the "Company")

 

INDEPENDENT JORC COMPLIANT RESOURCE ESTIMATE COMPLETE FOR THE MAXIMUS TARGET - ARAPUÁ FERTILIZER PROJECT

 

Harvest Minerals Limited (AIM:HMI) is pleased to announce that an independent Indicated Mineral Resource estimate (Resource estimate) has been completed for the Company's 100% owned Arapuá Fertilizer Project (Project) in Minas Gerais State, Brazil.

The Resource estimate, based on an air core drilling programme of only the weathered kamafugite, is JORC 2012 Compliant and is part of an ongoing technical report being compiled by GE21 Consultoria Mineral (GE21).  The Company anticipates announcing the results of the GE21 technical report in the current quarter.

 

The Company has conducted a drilling programme over an area covering approximately ~3% of the known mineralization not including the unweathered kamafugite underlying the resource. The rationale for the limited scope programme was to conserve cash and only identify sufficient resource for the immediate future.

The results of the drilling programme support Manangement's view that the Company is advancing towards development of a valuable product.

The limited scope drilling programme conducted at the Maximus target identified a JORC (2012) compliant total Indicated resource of 883Kt at 4.21% K2O and 3.53% P2O5 at a 3.5% K2O cut-off.  In the drilled area there is an estimated additional exploration potential of 3.0Mt to 3.5Mt of ore with K2O grades of 2.7% to 3.5%, to the base of the weathered kamafugite. 

 

The resource includes 202Kt at 5.24% K2O and 3.29% P2O5 (higher K2O) and 160Kt at 4.01% K2O and 4.62% P2O5 (higher P2O5).

Additionally, the total Indicated resource includes average grades of 6.34% CaO, 5.95% MgO, 0.33% MnO and 34.53% SiO2, which are important in developing a multi-nutrient direct application natural fertilizer (DANF).

Commenting on the resource estimate, Harvest Executive Chairman, Brian McMaster stated: 

 

"Completion of this resource provides a firm basis for developing the Maximus target into a DANF project. The higher grade K2O and P2O5 zones provide more than enough material for us to commence trial mining and develop our product over the coming months. With this aim in mind we have already started a scoping study to delineate the potential economics of the project, requested quotes from potential contractors, started testwork on defining our initial product and applied for a trial mining permit. We will update shareholders as results are received as we develop into a significant South American fertilizer company."

 

Enquiries:

Harvest Minerals Limited

 

Brian McMaster, Chairman

Tel: +61 8 9200 1847

 

Strand Hanson Limited (Nominated & Financial Adviser)

Rory Murphy

James Spinney

Ritchie Balmer

Tel: +44 20 7409 3494

 

Mirabaud Securities LLP (Broker)

 

Beaufort Securities Ltd

(Joint Broker)

 

Buchanan

(Financial PR)

 

Rory Scott

 

 

Jon Bellis

 

 

Bobby Morse

Anna Michniewicz

 

Tel: + 44 20 7878 3360

 

 

Tel: + 44 20 73828300

 

 

Tel: +44 20 7466 5000

 

 

Background

The Arapua Fertilizer Project is strategically located in the Brazilian Cerrado, 360km NW from Belo Horizonte, the capital of Minas Gerais State. The project consists of seven granted exploration licenses covering total area of 12,997.6 hectares, divided across both the Arapuá and Maximus targets.

Previous geological mapping at Maximus has identified a continuous kamafugite rock layer containing both phosphate and potassium, over an area of approximately 1.691 km2.

The air core drilling programme detected widespread weathered kamafugite rocks with mineralized interceptions ranging from 4.0m to 24.0m in thickness and grades between 1.67% to 4.27% P2O5 and from 2.16% to 5.30% K2O.

In addition to the phosphate and potassium oxide mineralization, grades of CaO (ranging from 0.80% to 15.60%), MgO (ranging from 3.21% to 17.90%), MnO (ranging from 0.18% to 0.55%) and silicon dioxide (SiO2) (ranging from 27.70% to 41.00%) were detected in the kamafugite weathered rocks. These results corroborate the potential of the kamafugite as a multi-nutrient silicate agro-mineral which could produce a direct application natural fertilizer (DANF).

Geological Model

At Maximus, the multi-nutrient mineralization, including K2O, P2O5, CaO, MgO and SiO2 occurs in weathered kamafugitic rocks which were targeted in the air core drilling programme carried out in early 2016;

 

All the available geological mapping, topographic and drilling data was used in the 3D geological modeling. Together with independent consultants GE21, the Company constructed a geological model through the interpretation of vertical sections based on the drill holes, using lines and polygons to generate solids (wireframes).

 

The contact between the weathered and unweathered kamafugite was defined based on the available drill log information. The top contact between the underlying sandstone layer (Areado Group) and the bottom of the laterite layer was interpolated from all available data.

 

In total, three mineralized layers were modeled, which reflect three distinct mineralization types as classified by grade. The first layer reflects the lower grade kamafugite saprolite (lg_sap), whereas layer 02 and 03 reflect the higher grade K2O (hg K2O) and P2O5 (hg P2O5) respectively.

 

Figure 01 illustrate a typical geological cross section of the modeled layers.

 

http://www.rns-pdf.londonstockexchange.com/rns/1782F_-2016-7-25.pdf

 

Mineral Resource

Block models were developed for each of the three mineralized layers (Figure 02) and the resource was estimated using Ordinary Kriging (OK) with the results validated with a comparative Nearest Neighbor estimation (NM). A 3.5% K2O cut-off grade was applied to the resource estimate which was categorized as Indicated with a total global resource of 883kt @ 4.21% K2O and 3.53 P2O5 (Table 01).

http://www.rns-pdf.londonstockexchange.com/rns/1782F_-2016-7-25.pdf

 

Block Model: 25m x 25m x 6m (12.5m x 12.5m x 3m) - 3.5% K2O cutoff grade applied

Layer

Tonnage (kt)

K2O %

P2O5%

CaO%

MgO%

MnO%

SiO2%

LOI %

1 - LG_sap

521

3.88

3.28

6.48

6.30

0.33

34.28

5.95

2 - HG K2O

202

5.24

3.29

5.56

5.45

0.34

35.77

4.74

3 - HG P2O5

160

4.01

4.62

6.85

5.44

0.33

33.75

5.48

Total Indicated

883

4.21

3.53

6.34

5.95

0.33

34.52

5.59

Table 01 - Maximus Target - Mineral Resources (JORC 2012).

 

GE21 estimated an exploration potential for material within the drilled areas, but below the 3.5% cut-off grade of between 3.0 to 3.5Mt with average grades from 2.7 to 3.5% K2O, by applying a cut off grade of 1%.

As only a small area was drilled corresponding to approximately 3% of the total area of the geological-geophysical potential, the exploration potential remains open at depth and in several directions (Figure 03).

 

http://www.rns-pdf.londonstockexchange.com/rns/1782F_-2016-7-25.pdf

 

COMPETENT PERSON STATEMENT

The information in this statement which relates to the Mineral Resource and Exploration Target is based on information compiled by Mr. Bernardo H C Viana who is a geologist and full time director and owner of GE21 and is registered as Competent Person in the AIG (Australian Institute of Geoscientists). Mr. Bernardo Viana has sufficient relevant experience to the style of mineralization to qualify as a Competent Person as defined in the JORC Code (2012). Mr. Viana also meets the requirements of a qualified person under the AIM Note for Mining, Oil and Gas Companies.

CAUTIONARY STATEMENTS

The Company's Exploration Target includes potential quantity and grade and is conceptual in nature. There has been insufficient exploration to define these mineral resources and it is uncertain if further exploration will result in the determination of mineral resources.

The reader is cautioned that a Mineral Resource is an estimate only and not a precise and completely accurate calculation, being dependent on the interpretation of limited information on the location, shape, and continuity of the occurrence and on the available sampling results. Actual mineralisation can be more or less than estimated depending upon actual geological conditions. Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability. No Mineral Reserves are being stated.

JORC Code, 2012 Edition - Table 1 report template

Section 1 Sampling Techniques and Data

(Criteria in this section apply to all succeeding sections.)

 

 

 

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.

·    Each air core drill hole was sampled using a 1 meter interval. Samples were collected directly in the cyclone and identified according to the hole number and depth. The cyclone was systematically cleaned at each 1 meter drilled.

·    Samples were prepared at the company´s field facilities and included, drying, crushing, screening at 4mm, homogenization and splitting. A small portion of approximately 250gr, representative of each 1m interval sample, was collected for archive.

·    Samples for lab analysis had been composed in intervals varying from a minimum 1 m to a maximum of 4 m, in compliance with the geological description.

·    QA/QC samples, including reference materials, blanks, and duplicates, were systematically introduced in the batches to the lab at a nominal rate of 2:10.

·    The location of each air core drill hole was registered with the help of a hand-held GPS Garmin model 62sc and the coordinates were recorded on UTM_WGS84, zone 23 south.

·    All the samples were collected at 1m intervals and were utilised for geological logging.

·    Samples for lab analysis, weighing 1.5 to 2 kg, had been split into intervals varying from minimum 1 m to maximum 4 m, in compliance to the geological description.

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).

·    Air core rig Mantis 80 mounted on a 6 x 6 Toyota Landcruiser. Hole diameter of standard NQ size.

 

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.

·    Samples were logged by geologist at the company field facilities.

·    Samples were collected directly in the cyclone and identified according to the hole number and depth. The cyclone was systematically cleaned at each 1 meter drilled.

·    Samples collected were systematically weighed, after being dried, at the company field facilities.

·    In general, the sample recoveries were high within the mineralised zones. No significant bias is expected.

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.

·    Air core samples had been logged considering the limitation of the drilling method.

·    Air core drill holes intersected strongly weathered kamafugite rock. Despite the weathering conditions, all the intervals were logged in the best way that was possible.

·    All samples from air core drilling were logged.

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 samples from air core drilling were logged.

·    The entire air core samples were collected. Samples were dried, crushed, screened, homogenized and split.

·    Samples for lab analysis were prepared at intervals varying from a minimum 1 m to a maximum 4 m, in compliance with the geological description.

·    Samples were dried, crushed, screened, homogenized and split.

·    The quality of the prepared samples, weighting 1.5 kg to 2.0 kg, used for analysis is considered appropriate at the actual stage of exploration.

·    Assays are reported as part of this announcement.

·    Results for QA/AC samples, including blanks, duplicates and standards, are totally inside the expected range.

·    Sample sizes (1kg to 8kg) are considered to be of a sufficient size to accurately represent the key fertilizer elements, based on the near-surface mineralisation style, the width and continuity of the intersections at shallow depths and the sampling methodology.

 

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 analyses were conducted at the SGS Geosol lab, located in Belo Horizonte, Brazil. The assay package used for all samples sent to SGS laboratories was XRF79C-10. X-ray Fluorescence equipment was used for the assay measurements. The results comprise the grades for oxides (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2, TiO2).

·    No geophysical techniques, spectrometers etc were used in the analysis.

·    Industry standard certified reference materials (CRMs) and blanks were utilized in order to check laboratory assay quality control.

·    QA/QC samples, including reference materials, blanks, and duplicates, were systematically introduced in the batches to the lab in nominal rate of approximately 2:10.

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.

·    The company geologist identified the appropriate sample intervals, based on core logs.

·    No twinned hole had been drilled at this stage.

·    A comprehensive library of protocols were produced and stored in electronic storages.

·    No adjustments have been made to the assay data.

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.

·    The location of each air core drill hole was registered with the help of a hand-held GPS Garmin model 62CSX Map and the coordinates were recorded on System UTM, Datum WGS84, zone 23 south.

·    No down-hole survey was performed considering that all holes are vertical and no deep.

·    Co-ordinates are presented in datum WGS84, System UTM Zone 23S.

·    A topographic survey was conducted in an area of approximately 116,340 m2 with measurement points distribute in a grid of 50m x 50m. A total of 86 measured points, including the 25 drill hole locations, were surveyed using pair of differential GPS system (DGPS) with an planimetric and altimetric accuracy of 0.005 m and 0.008 m, respectively.

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.

·    Air core drill holes were spaced of approximately 50 m.

·    Drill spacing is adequate to define the geological and grade continuity for Mineral Resource estimation. Classification has taken into account drilling type, drill spacing, data quality and production data.

·    Sample lengths within the database are not composited. Sample compositing was applied to data extracts for statistical analysis and Mineral Resource modelling.

,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.

·    The air core drill holes were located at the western side of Serra do Maxixe Plateau within the potential geological unit, which is sub-horizontal.

·    There is no relationship with mineralized structure. The target is a sub-horizontal unit which is strongly weathered close to surface, sometimes reaching 25 metres depth.

·    No sampling bias is recognized as a result of drilling orientation and mineralized strata.

Sample security

·    The measures taken to ensure sample security.

·    Drilling and sample custody were supervised by company technical team.

·    Each sample was been bagged in an appropriate numbered plastic bag and sealed. A sample card with the sample identification was placed inside the sample bag.

·    Samples are stored on site at a fenced and gated facility until collected for transport to SGS laboratory in Belo Horizonte.

·    Tracking sheets are available to track sample progress.

Audits or reviews

·    The results of any audits or reviews of sampling techniques and data.

·    GE21 performed a database audit in May 2016 with site review of geologic processes, production sampling and process control. All available assay certificates from the SGS laboratory were compared to the database.

·    GE21 is of the opinion that the QA/QC indicates the information collected is acceptable, and the database can be used for Mineral Resource estimation.

Section 2 Reporting of Exploration Results

(Criteria listed in the preceding section also apply to this section.)

 

 

 

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.

·    The Arapua Project comprises seven exploration licenses covering a total area of 12,997.6 hectares.

·    The mineral properties at Arapua Project are registered under the following processes; 832.447/2009, 832.448/2009, 832,451/2009, 831.144/2010, 831.145/2010, 831.146/2010 and 831.275/2010.

·    All tenements are granted exploration licenses.

 

Exploration done by other parties

·    Acknowledgment and appraisal of exploration by other parties.

·    Very limited work was conducted by the original owners and limited to regional mapping and few rock analysis, using a hand held XRF equipment.

Geology

·    Deposit type, geological setting and style of mineralisation.

·    Potash-phosphate enrichment associated with ultrapotassic rocks (Arapuá Project).

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:

o easting and northing of the drill hole collar

o elevation or RL (Reduced Level - elevation above sea level in metres) of the drill hole collar

o dip and azimuth of the hole

o down hole length and interception depth

o 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.

·    To date, a total of 25 air core drill holes have been drilled.

·    Coordinates are presented in datum WGS84, System UTM Zone 23S.

·    All holes were vertical so no dip or azimuth measurements were taken.

·    All holes intersected weathered mineralisation throughout the whole and were stopped in mineralisation.

·    Production drilling and surface mapping was available for the construction of the geological and Mineral Resource model.

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.

·    Mineralized intersections were aggregated based on the weighted arithmetic mean.

·    A cut-off grade of 3.5% K2O was used.

·    No metal equivalent values have been used.

 

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').

·    The mineralization occurs related to a sub-horizontal unit which is strongly weathered close to surface, sometimes reaching 25 metres depth.

 

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.

·    Refer to Figures in body of text.

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.

·    Based on the fact that exploration results reported for the Arapuá Project to date allow a resource estimation within mineral reserve classified as indicated, involving an air core drill holes grid, geochemical and geological data, the report is considered to be sufficiently balanced.

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.

·    No other exploration data is considered material to this release at this stage.

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.

·    Agronomic efficiency tests.

·    Trial Mining.

·    Extension of air core drilling program.

 

 

Section 3 Estimation and Reporting of Mineral Resources

(Criteria listed in section 1, and where relevant in section 2, also apply to this section.)

 

 

 

Database integrity

·    Measures taken to ensure that data has not been corrupted by, for example, transcription or keying errors, between its initial collection and its use for Mineral Resource estimation purposes.

·    Data validation procedures used.

·    Data extracted from the database for Mineral Resource estimation purposes was run through general checks to ensure data is valid. GE21 performed an audit on the database on April 2016. The audit compared scans of original drill logs (lithology, sampling, results) to values contained in the database and also with the core and annotations on the chip boxes. The audit also electronically compared assay results supplied directly from SGS Geosol to the database.

·    Checks on data include sensible ranges of values for attributes, drill hole collars matching topography and with expected limits, overlapping sample intervals, depths, azimuths, dips and co-ordinates for consistency. Any inconsistent information is either modified or excluded from use in estimation.

·    There are no significant problems found in the database.

Site visits

·    Comment on any site visits undertaken by the Competent Person and the outcome of those visits.

·    If no site visits have been undertaken indicate why this is the case.

·    Mr. Bernardo H C Viana which is registered as Competent Person in the AIG (Australian Institute of Geoscientists) visited the project area and core shed between April 18th and 20th, 2016.

·    As part of the external audit, field locations for 25 historic drill collars were collected and compared to database coordinates.

·    Drill hole location and data materiality and the conceptual geological model have been validated. Sampling procedures were also validated.

 

Geological interpretation

·    Confidence in (or conversely, the uncertainty of ) the geological interpretation of the mineral deposit.

·    Nature of the data used and of any assumptions made.

·    The effect, if any, of alternative interpretations on Mineral Resource estimation.

·    The use of geology in guiding and controlling Mineral Resource estimation.

·    The factors affecting continuity both of grade and geology.

·    The geologic model level of confidence is considered moderate to good, with information available from 25 drill holes.

·    The data used for the geologic model included all the information available from air core drilling.

·    The limits of mineral resources were determined using the drill hole information.

·    The continuity of modelled potential zone was based on drill hole information and interpretation results from surface mapping, ground magnetic and ground radiometric surveys.

Dimensions

·    The extent and variability of the Mineral Resource expressed as length (along strike or otherwise), plan width, and depth below surface to the upper and lower limits of the Mineral Resource.

·    The Mineral Resource extends 450m in the southwest/northeast direction by roughly 160m northwest/southeast.

·    Three mineralized layers, reflecting three distinct mineralization types in terms of variable grades, were modelled for Maximus target. The layer 01 reflect the kamafugito saprolite with low grade, layer 02 refers to the saprolite with high grade of K2O and layer 03 refers to the saprolite with high grade of P2O5.

Estimation and modelling techniques

·    The nature and appropriateness of the estimation technique(s) applied and key assumptions, including treatment of extreme grade values, domaining, interpolation parameters and maximum distance of extrapolation from data points. If a computer assisted estimation method was chosen include a description of computer software and parameters used.

·    The availability of check estimates, previous estimates and/or mine production records and whether the Mineral Resource estimate takes appropriate account of such data.

·    The assumptions made regarding recovery of by-products.

·    Estimation of deleterious elements or other non-grade variables of economic significance (eg sulphur for acid mine drainage characterisation).

·    In the case of block model interpolation, the block size in relation to the average sample spacing and the search employed.

·    Any assumptions behind modelling of selective mining units.

·    Any assumptions about correlation between variables.

·    Description of how the geological interpretation was used to control the resource estimates.

·    Discussion of basis for using or not using grade cutting or capping.

·    The process of validation, the checking process used, the comparison of model data to drill hole data, and use of reconciliation data if available.

·    The resource estimation was performed on the K2O wt%, P2O5 wt%, CaO w%, MgO w% and SiO2 w% variables.

·    Resources were estimated using 3.5% K2O cut-off grade.

·    The tonnages and grades were estimated based on the volume estimate calculated from a Gemcom Surpac wireframe model of the project to which the average density and weighted average K2O, P2O5, CaO, MgO and SiO2  grades of each drill hole was applied.

·    No previous estimates were conducted in the project.

·    No assumptions were made regarding recovery of by-products.

·    No assumptions were made regarding these elements.

·    Air core drill holes were spaced of approximately 50 m. A block model was created for the Mandacaru Project area in using a parent block of 25mE x 25mN x 6mRL with sub-blocks of 12.5mE x 12.5mN x 3mRL in all mineralized layers.

·    No assumptions were made regarding selective mining units.

·    Exploratory data analyses (EDA) showed that mineralization is constrained by weathered kamafugitic rock type and take into consideration the variables K2O, P2O5, CaO, MgO, SiO2, Fe2O3, Al2O3 and LOI.

·    The method used for the estimate was Ordinary Kriging (OK). Validation of estimated grades was carried out with a comparative Nearest Neighbour estimation (NM).

Moisture

·    Whether the tonnages are estimated on a dry basis or with natural moisture, and the method of determination of the moisture content.

·    Tonnages are estimated on a dry basis.

Cut-off parameters

·    The basis of the adopted cut-off grade(s) or quality parameters applied.

·    The cut-off grade for resource was determined at 3.5% of K2O based on the deposit interceptions.

Mining factors or assumptions

·    Assumptions made regarding possible mining methods, minimum mining dimensions and internal (or, if applicable, external) mining dilution. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential mining methods, but the assumptions made regarding mining methods and parameters when estimating Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the mining assumptions made.

·    No assumptions were made regarding mining factors.

Metallurgical factors or assumptions

·    The basis for assumptions or predictions regarding metallurgical amenability. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider potential metallurgical methods, but the assumptions regarding metallurgical treatment processes and parameters made when reporting Mineral Resources may not always be rigorous. Where this is the case, this should be reported with an explanation of the basis of the metallurgical assumptions made.

·    No assumptions were made regarding metallurgical factors.

·    No assumptions were made regarding metallurgical tests.

Environmen-tal factors or assumptions

·    Assumptions made regarding possible waste and process residue disposal options. It is always necessary as part of the process of determining reasonable prospects for eventual economic extraction to consider the potential environmental impacts of the mining and processing operation. While at this stage the determination of potential environmental impacts, particularly for a greenfields project, may not always be well advanced, the status of early consideration of these potential environmental impacts should be reported. Where these aspects have not been considered this should be reported with an explanation of the environmental assumptions made.

·    No assumptions were made regarding environmental factors.

 

Bulk density

·    Whether assumed or determined. If assumed, the basis for the assumptions. If determined, the method used, whether wet or dry, the frequency of the measurements, the nature, size and representativeness of the samples.

·    The bulk density for bulk material must have been measured by methods that adequately account for void spaces (vugs, porosity, etc), moisture and differences between rock and alteration zones within the deposit.

·    Discuss assumptions for bulk density estimates used in the evaluation process of the different materials.

·    Bulk density determinations were made on representative kamafugite saprolite sample at each one of the 25 holes location.

·    An estimated variable density by Distance Square method was performed for the mineralized bodies and the wall rock.

Classification

·    The basis for the classification of the Mineral Resources into varying confidence categories.

·    Whether appropriate account has been taken of all relevant factors (ie relative confidence in tonnage/grade estimations, reliability of input data, confidence in continuity of geology and metal values, quality, quantity and distribution of the data).

·    Whether the result appropriately reflects the Competent Person's view of the deposit.

·    Mineral Resources were classified as Indicated resources based on the on the assessment of the data, geological interpretation, quality of grade estimation and type of mineralization.

·    Drill hole spacing varies is approximately 50m.

·    Results reflect the Competent Persons' view of the deposit.

·    The Maximus Target contains a JORC (2012) compliant total resource of 0.88Mt @ 3.53% P2O5 / 4.21% K2O, including 0.20Mt @ 3.29% P2O5 / 5.24% K2O and 0.16Mt @ 4.01% P2O5 / 4.62% K2O.

·    The drilled area has an estimated additional exploration potential of 3.5Mt with lower K2O grades, ranging from 2.7% to 3.5%, which need to be best investigated.

 

Audits or reviews

·    The results of any audits or reviews of Mineral Resource estimates.

·    No audit of the estimate has been undertaken.

Discussion of relative accuracy/ confidence

·    Where appropriate a statement of the relative accuracy and confidence level in the Mineral Resource estimate using an approach or procedure deemed appropriate by the Competent Person. For example, the application of statistical or geostatistical procedures to quantify the relative accuracy of the resource within stated confidence limits, or, if such an approach is not deemed appropriate, a qualitative discussion of the factors that could affect the relative accuracy and confidence of the estimate.

·    The statement should specify whether it relates to global or local estimates, and, if local, state the relevant tonnages, which should be relevant to technical and economic evaluation. Documentation should include assumptions made and the procedures used.

·    These statements of relative accuracy and confidence of the estimate should be compared with production data, where available.

·    Estimated grades were compared to a nearest neighbour model to check for global bias. The bias obtained for estimated variables in the axis E, N and RL were considered within acceptable ranges.

·    No trends in the grade estimates were identified by plotting the mean values from the nearest neighbour estimate versus the kriged results for Indicated blocks in east-west, north-south and vertical swaths.

·    There are no production data to be compared.

 


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