Highly successful EM survey identifies multiple conductors

ASX Announcement 30 April, 2018

Highly successful EM survey identifies multiple conductors at Mt Venn copper-

nickel-cobalt project In light of the number and strength of these conductors, Great Boulder will

immediately undertake a ground-based EM survey to identify drilling targets

Great Boulder Resources (ASX: GBR) is pleased to announce the outstanding results of the highly successful airborne EM survey conducted over the Eastern Mafic complex at its Mt Venn copper-nickel-cobalt project in WA.

The survey has identified multiple, conductors over a 6km strike length. Importantly, these conductors are considered highly prospective because of their ‘late-time’ EM response, which is indicative of a bedrock source.

The Eastern Mafic complex sits next to the Mt Venn discovery, where copper, nickel and cobalt mineralisation has been identified over several kilometres of strike.

Mineralisation at Mt Venn, which remains open in every direction, is copper dominant and indicative of late-stage formation within the intrusion. The Eastern Mafic complex was targeted because its geochemical signature suggested an earlier stage of formation, meaning it is potentially closer to the source of the intrusion and therefore prospective for massive sulphide mineralisation.

Great Boulder confirmed by a gravity survey the Eastern Mafic is part of a large intrusive body and the latest EM survey shows this body contains several large, strong conductors.

In addition, preliminary XRF analysis of aircore drilling over the Eastern Mafic complex has demonstrated anomalous copper and nickel coincident with the airborne EM conductors. These results support Great Boulder’s view that the Eastern Mafic complex has the potential to host significant massive sulphide mineralisation.

A ground-based moving loop EM (“MLEM”) survey will now be undertaken to better define drilling targets. MLEM was used successfully at Mt Venn to define conductor plates which led to the discovery of the copper, nickel and cobalt mineralisation.

The MLEM crew is currently mobilising to site and will initially focus on the strongest late-time conductors identified in the airborne EM survey.

The MLEM survey will enable the conductor plates to be ranked on strength and final geochemistry from the aircore drilling, with a maiden RC drill program planned to target copper-nickel-cobalt sulphide mineralisation at the Eastern Mafic complex.

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30 April, 2018

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Great Boulder Managing Director Stefan Murphy said the results of the airborne EM survey

are highly promising.

“These results reveal an exceptionally large number of strong late-time conductors which show the Eastern Mafic complex has the potential to host significant massive sulphide mineralisation,” Mr Murphy said.

“We have now identified over 25 discrete, late-time conductors located in a part of the intrusion previously identified as having elevated copper, nickel and cobalt. This geochemical anomalism has been confirmed with preliminary XRF field assays, extending the copper-nickel-cobalt footprint to over 4km in the core of the intrusion and even further along the eastern shear zone.”

Airborne EM late-time (Channel 30) response. Core of the intrusion has the greatest concentration of strong

conductors over 4km strike with more conductors located along the eastern shear zone

ASX Announcement

30 April, 2018

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Airborne EM Survey Details

The airborne EM survey covered 55sqkm and targeted massive sulphide mineralisation associated with mafic intrusions in the Eastern Mafic complex. Over 400 line kilometres were flown by helicopter on 150m spaced east-west lines at an approximate height of 30m. An additional five lines were flown north-south to ensure key features with an east-west orientation were not missed.

The airborne EM survey has been highly successful in identifying late-time conductors, indicative of a bedrock source. The conductors are concentrated within the core of the intrusive complex, in an area of dense rock identified in the gravity survey and interpreted to represent discrete mafic intrusions. This same area is associated with elevated copper, nickel and cobalt mineralisation (see ASX Announcement 14 March 2018).

The EM conductors are much more extensive than initially anticipated, with the core of the intrusion hosting a 4km long x 1.5km wide trend of conductors. Within this trend subtle differences are seen, with some conductors on the edge of the intrusion also highly magnetic (conductors 1-4), while other conductors in the centre of the intrusion showing little or no magnetic response (conductors 5-10). All priority conductors will be tested with MLEM.

A separate trend of conductors has been identified along a major northwest orientated structure that marks the eastern boundary of the intrusive complex. These conductors also exhibit a late-time response and are associated with a gravity high that runs along the structure.

The west survey area has encountered paleochannels that cut the prospective intrusive units and mask potential bedrock conductors.

Aircore geochemistry drilling over this area has also identified distinct copper-nickel anomalies in the bedrock that indicate potential bedrock sources of the mineralisation that cannot be detected through the conductive cover. Powerful ground MLEM will be used to test for bedrock conductors beneath this cover.

AEM survey being flown over the Eastern Mafic complex

https://www.asx.com.au/asxpdf/20180314/pdf/43sdtld2hk44c3.pdf

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30 April, 2018

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Preliminary Aircore Geochemistry

Great Boulder completed a 226 hole aircore drilling program over the Eastern Mafic complex to map bedrock geochemistry and determine areas of elevated copper, nickel and cobalt. End of hole samples have been submitted for multi-element laboratory analysis, however Great Boulder routinely checked end of hole and 4m downhole composites with a portable XRF to provide live geochemical data.

Where aircore drilling crosses or is in close proximity to a conductor, there is a strong correlation between elevated copper-nickel values and the conductor. Great Boulder considers the portable XRF results provide a valuable geochemical guide but given the lack of adequate sample preparation are not considered definitive. Laboratory assay results for the aircore program are expected in the next three weeks and will be used to help plan priority RC drill targets.

Aircore geochemistry used in conjunction with airborne and ground EM has worked

exceptionally well at Mt Venn in discovering copper-nickel sulphide mineralisation. The

preliminary XRF results from the Eastern Mafic complex shows a strong correlation (as

highlighted at Conductor 6) and will be used for prioritising conductors for drilling

Aircore holes drilled near Conductors 1 and 3 encountered very hard ground conditions from

surface and only penetrated between 2-7m before blade refusal, potentially not reaching the

target mafic intrusion.

Aircore maximum downhole copper (left) and nickel (right) over late-time (channel 30) airborne EM image

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MLEM Plan

A detailed ground MLEM survey will now commence on the strongest conductors within the Eastern Mafic complex.

The majority of late-time conductors are located within a 4km long x 1.5km wide trend associated with the dense core of the Eastern Mafic complex and coincident copper-nickel anomalism. These conductors will be surveyed on a 100m x 50m station spacing with infill to 25m stations. The data will be used to generate conductor plates for drill hole targeting.

Three conductors associated with the eastern shear zone will initially be tested with single

MLEM lines at 50m station spacing. Depending on results, additional lines may be

planned to better define conductor plates for drill testing.

A paleochannel that cuts the western side of the eastern mafic complex has resulted in a

wide paleo “valley” with significantly deeper weathering that would mask potential bedrock

conductors. A wide spaced 200m line x 100m station MLEM survey will be completed

over this area in order to detect anomalies beneath the conductive cover.

Bouguer gravity image (left) and late-time (channel 30) airborne EM image (right) with MLEM station plan. Core of the

intrusion with priority conductors is outlined in red, eastern shear zone conductors outlined in purple

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Competent Person’s Statement

Exploration information in this Announcement is based upon work undertaken by Mr Stefan Murphy whom is a Member of the Australasian Institute of Geoscientists (AIG). Mr Stefan Murphy has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is 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’ (JORC Code). Mr Stefan Murphy is an employee of Great Boulder and consents to the inclusion in the report of the matters based on their information in the form and context in which it appears.

Forward Looking Statements

This Announcement is provided on the basis that neither the Company nor its representatives make any warranty (express or implied) as to the accuracy, reliability, relevance or completeness of the material contained in the Announcement and nothing contained in the Announcement is, or may be relied upon as a promise, representation or warranty, whether as to the past or the future. The Company hereby excludes all warranties that can be excluded by law. The Announcement contains material which is predictive in nature and may be affected by inaccurate assumptions or by known and unknown risks and uncertainties and may differ materially from results ultimately achieved.

The Announcement contains “forward-looking statements”. All statements other than those of historical facts included in the Announcement are forward-looking statements including estimates of Mineral Resources. However, forward-looking statements are subject to risks, uncertainties and other factors, which could cause actual results to differ materially from future results expressed, projected or implied by such forward-looking statements. Such risks include, but are not limited to, copper, gold and other metals price volatility, currency fluctuations, increased production costs and variances in ore grade recovery rates from those assumed in mining plans, as well as political and operational risks and governmental regulation and judicial outcomes. The Company does not undertake any obligation to release publicly any revisions to any “forward-looking statement” to reflect events or circumstances after the date of the Announcement, or to reflect the occurrence of unanticipated events, except as may be required under applicable securities laws. All persons should consider seeking appropriate professional advice in reviewing the Announcement and all other information with respect to the Company and evaluating the business, financial performance and operations of the Company. Neither the provision of the Announcement nor any information contained in the Announcement or subsequently communicated to any person in connection with the Announcement is, or should be taken as, constituting the giving of investment advice to any person.

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Appendix 1 – Aircore drill hole location and handheld XRF copper and nickel geochemical analysis

End of Hole Max. Downhole

Hole ID Easting Northing Depth Cu (ppm) Ni (ppm) Cu (ppm) Ni (ppm)

18MVAC001 554540 6884619 57 44 114 75 368

18MVAC002 554697 6884618 45 16 29 37 76

18MVAC003 554860 6884623 28 53 408 72 617

18MVAC004 555013 6884613 22 47 34 72 63

18MVAC005 555147 6884612 7 19 37 38 95

18MVAC006 555232 6884616 21 692 393 692 991

18MVAC007 555339 6884618 10 170 93 175 204

18MVAC008 555429 6884619 14 104 36 224 223

18MVAC009 555539 6884618 36 12 41 53 67

18MVAC010 555633 6884623 25 21 25 44 71

18MVAC011 555740 6884622 6 615 412 615 452

18MVAC012 555834 6884614 7 25 160 66 206

18MVAC013 555947 6884617 8 42 30 109 31

18MVAC014 556037 6884615 4 89 29 89 30

18MVAC015 556139 6884610 16 27 26 39 30

18MVAC016 556244 6884618 12 35 28 54 30

18MVAC017 556329 6884609 5 30 0 30 34

18MVAC018 556403 6884624 2 91 0 91 35

18MVAC019 556467 6884618 7 18 17 23 38

18MVAC020 556537 6884613 8 0 19 35 34

18MVAC021 556636 6884621 4 59 35 59 35

18MVAC022 556737 6884620 5 30 27 30 29

18MVAC023 556825 6884618 13 51 25 52 34

18MVAC024 556919 6884612 16 32 22 40 32

18MVAC025 557021 6884612 25 255 114 255 160

18MVAC026 557179 6884621 15 53 587 100 726

18MVAC027 557340 6884614 26 47 78 52 150

18MVAC028 557497 6884616 63 103 116 248 116

18MVAC029 557658 6884613 54 0 366 79 366

18MVAC030 557738 6884619 42 51 72 81 72

18MVAC031 557819 6884624 39 52 75 106 470

18MVAC032 557894 6884619 38 61 88 1547 327

18MVAC033 557978 6884619 20 1373 246 2065 417

18MVAC034 558059 6884617 51 70 121 1561 469

18MVAC035 558135 6884621 39 30 46 803 155

18MVAC036 558223 6884626 42 202 163 207 512

18MVAC037 558295 6884617 57 282 640 287 640

18MVAC038 558379 6884612 31 1630 327 1630 700

18MVAC039 554303 6885266 33 88 451 126 493

18MVAC040 554419 6885261 26 90 481 114 519

18MVAC041 554504 6885261 28 31 1466 69 1651

18MVAC042 554619 6885264 9 70 217 88 217

18MVAC043 554779 6885260 19 0 27 26 40

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18MVAC044 554937 6885259 6 0 0 35 99

18MVAC045 555100 6885256 5 31 49 31 49

18MVAC046 555259 6885259 17 45 1006 78 1006

18MVAC047 555420 6885261 28 52 117 91 117

18MVAC048 555599 6885259 13 13 22 37 44

18MVAC049 555736 6885258 13 24 35 28 81

18MVAC050 555901 6885258 17 33 101 33 101

18MVAC051 556075 6885253 6 9 26 9 33

18MVAC052 556218 6885259 4 18 41 18 41

18MVAC053 556380 6885265 6 39 23 39 33

18MVAC054 556540 6885262 19 27 0 53 48

18MVAC055 556698 6885263 13 0 20 27 48

18MVAC056 556778 6885255 6 7 17 28 19

18MVAC057 556940 6885262 5 42 23 42 34

18MVAC058 557030 6885256 7 16 50 25 54

18MVAC059 557161 6885257 7 45 49 45 51

18MVAC060 557318 6885258 16 1894 73 2689 140

18MVAC061 557495 6885260 37 36 67 272 145

18MVAC062 557658 6885256 58 61 45 216 82

18MVAC063 557819 6885264 35 31 28 212 80

18MVAC064 557981 6885255 28 171 175 171 260

18MVAC065 558141 6885256 9 102 100 1449 100

18MVAC066 558301 6885259 9 145 131 145 131

18MVAC067 558461 6885260 10 31 40 31 40

18MVAC068 558605 6885260 18 89 488 100 551

18MVAC069 558782 6885257 4 116 379 116 379

18MVAC070 556558 6885901 8 35 1674 46 1674

18MVAC071 556722 6885898 3 27 56 27 56

18MVAC072 556818 6885898 11 233 79 243 79

18MVAC073 556933 6885900 4 45 27 45 27

18MVAC074 557018 6885899 8 16 23 21 25

18MVAC075 557122 6885902 5 139 47 139 47

18MVAC076 557201 6885898 4 16 0 16 17

18MVAC077 557358 6885899 14 1895 103 1895 103

18MVAC078 557497 6885903 8 44 42 113 42

18MVAC079 557772 6885901 4 56 40 56 40

18MVAC080 557858 6885904 4 22 32 22 32

18MVAC081 558161 6885899 3 109 44 109 44

18MVAC082 558318 6885898 2 62 49 62 49

18MVAC083 558458 6885900 5 20 17 20 17

18MVAC084 558638 6885896 5 48 53 48 53

18MVAC085 558804 6885897 6 23 25 23 26

18MVAC086 557279 6883817 51 79 58 760 417

18MVAC087 557275 6883977 52 40 29 107 74

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18MVAC088 557276 6884137 42 64 39 590 235

18MVAC089 557279 6884297 47 0 0 94 78

18MVAC090 557283 6884455 77 195 272 360 272

18MVAC091 557284 6884697 47 82 61 144 157

18MVAC092 557281 6884858 39 28 49 237 169

18MVAC093 557279 6885178 22 119 45 180 89

18MVAC094 557280 6885333 8 23 18 39 24

18MVAC095 557284 6885501 5 39 55 39 55

18MVAC096 557284 6885660 4 24 23 24 25

18MVAC097 557280 6885825 8 31 28 31 32

18MVAC098 557279 6885968 4 191 101 191 101

18MVAC099 557276 6886112 3 29 38 29 42

18MVAC100 557277 6886286 3 33 26 33 36

18MVAC101 557277 6886463 11 51 38 51 38

18MVAC102 558849 6885252 7 114 404 130 432

18MVAC103 558698 6885261 6 103 550 116 550

18MVAC104 558538 6885259 6 88 69 88 69

18MVAC105 558378 6885260 15 923 65 923 152

18MVAC106 558221 6885258 5 120 157 140 157

18MVAC107 554574 6885265 9 46 180 54 180

18MVAC108 554473 6885262 12 21 451 62 984

18MVAC109 554365 6885262 6 37 77 37 77

18MVAC110 554260 6885262 31 82 654 92 654

18MVAC111 558340 6884618 41 27 241 310 580

18MVAC112 558264 6884617 33 25 90 194 231

18MVAC113 558023 6884616 16 138 30 1545 463

18MVAC114 557939 6884620 23 782 138 3339 266

18MVAC115 557860 6884620 33 92 70 651 403

18MVAC116 557780 6884622 20 41 64 63 64

18MVAC117 557696 6884616 44 45 69 45 69

18MVAC118 557623 6884611 16 256 38 256 54

18MVAC119 559163 6884077 6 17 36 29 48

18MVAC120 559081 6884076 11 44 32 44 33

18MVAC121 559002 6884074 18 69 50 69 105

18MVAC122 558921 6884076 51 73 0 184 41

18MVAC123 558843 6884078 13 11 0 13 19

18MVAC124 558762 6884078 3 10 21 12 21

18MVAC125 558683 6884078 3 33 23 33 30

18MVAC126 558601 6884079 2 17 29 21 29

18MVAC127 558523 6884076 3 36 30 36 30

18MVAC128 558441 6884075 5 10 28 13 33

18MVAC129 558362 6884076 9 34 39 38 39

18MVAC130 558280 6884077 7 31 103 31 103

18MVAC131 558202 6884078 9 0 35 30 44

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18MVAC132 558121 6884077 11 37 36 53 47

18MVAC133 558041 6884076 7 10 13 15 29

18MVAC134 557963 6884077 21 33 34 33 42

18MVAC135 557883 6884077 3 74 90 74 90

18MVAC136 557803 6884078 26 52 107 216 263

18MVAC137 557720 6884077 8 177 63 147 71

18MVAC138 557641 6884078 24 14 27 366 147

18MVAC139 557561 6884078 18 126 39 126 39

18MVAC140 557481 6884080 45 40 51 62 56

18MVAC141 557319 6884080 39 95 205 306 205

18MVAC142 557159 6884080 61 69 100 316 115

18MVAC143 557001 6884080 81 45 52 135 236

18MVAC144 556839 6884080 60 32 30 53 53

18MVAC145 556759 6884080 54 49 73 49 73

18MVAC146 556680 6884078 66 10 47 53 47

18MVAC147 556598 6884079 53 33 29 55 36

18MVAC148 556518 6884077 59 30 32 268 52

18MVAC149 556442 6884078 54 12 0 96 54

18MVAC150 556360 6884079 50 70 0 70 50

18MVAC151 556280 6884080 45 29 17 98 47

18MVAC152 556203 6884080 54 381 69 381 219

18MVAC153 556125 6884079 60 18 27 197 186

18MVAC154 555962 6884079 57 17 29 49 45

18MVAC155 555800 6884074 50 50 72 68 131

18MVAC156 556697 6886535 8 33 22 33 23

18MVAC157 556861 6886539 3 18 54 23 54

18MVAC158 557020 6886538 6 24 29 24 29

18MVAC159 557182 6886537 2 37 32 37 32

18MVAC160 557341 6886541 4 0 0 18 37

18MVAC161 557502 6886539 3 42 49 42 49

18MVAC162 557660 6886541 33 213 23 213 41

18MVAC163 557816 6886541 11 17 23 33 28

18MVAC164 557977 6886538 20 119 27 119 31

18MVAC165 558139 6886540 19 23 29 30 29

18MVAC166 557270 6885017 19 166 86 170 90

18MVAC167 554000 6882619 123 40 125 40 125

18MVAC168 554317 6882619 93 36 134 36 134

18MVAC169 554474 6882620 69 32 32 33 32

18MVAC170 554555 6882619 71 509 542 509 542

18MVAC171 554637 6882617 59 272 84 452 617

18MVAC172 554719 6882619 60 37 114 39 114

18MVAC173 554797 6882619 72 47 99 117 149

18MVAC174 558578 6883396 54 7 68 60 91

18MVAC175 558402 6883398 59 8 84 65 152

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18MVAC176 558253 6883395 66 50 50 50 66

18MVAC177 558081 6883396 59 14 30 32 38

18MVAC178 557920 6883396 19 20 0 21 23

18MVAC179 557759 6883397 63 61 99 731 149

18MVAC180 557599 6883395 61 38 45 360 75

18MVAC181 557438 6883392 48 125 36 653 116

18MVAC182 557293 6883398 51 219 66 493 134

18MVAC183 557112 6883400 24 32 41 240 53

18MVAC184 556958 6883400 50 59 38 151 96

18MVAC185 556800 6883403 50 121 62 226 131

18MVAC186 556716 6883401 54 48 37 786 394

18MVAC187 556612 6883401 56 38 26 446 232

18MVAC188 556474 6883400 36 97 51 136 53

18MVAC189 556379 6883400 28 37 60 67 60

18MVAC190 556163 6883404 4 65 36 65 36

18MVAC191 555997 6883402 27 1362 242 1655 383

18MVAC192 557279 6882932 6 57 40 57 40

18MVAC193 557281 6883103 23 99 37 382 87

18MVAC194 557281 6883244 26 15 57 78 59

18MVAC195 557289 6883503 68 182 71 182 71

18MVAC196 559601 6882126 32 56 49 56 58

18MVAC197 559520 6882123 25 705 389 705 389

18MVAC198 559444 6882111 15 86 61 99 61

18MVAC199 559353 6882100 39 452 88 452 119

18MVAC200 559200 6882102 30 40 53 45 63

18MVAC201 559039 6882110 7 15 35 15 44

18MVAC202 558879 6882111 8 13 39 14 39

18MVAC203 558720 6882103 7 10 64 33 64

18MVAC204 558559 6882090 13 43 42 190 42

18MVAC205 558397 6882099 34 26 30 51 87

18MVAC206 558238 6882109 3 42 61 42 61

18MVAC207 558077 6882099 6 36 39 36 39

18MVAC208 557918 6882111 4 29 43 30 43

18MVAC209 557784 6882117 5 13 50 16 50

18MVAC210 557678 6882100 7 213 85 213 85

18MVAC211 557619 6882111 3 18 32 18 32

18MVAC212 557574 6882106 4 17 28 20 28

18MVAC213 557440 6882106 3 14 41 14 42

18MVAC214 557350 6882111 10 12 79 18 84

18MVAC215 557283 6882135 5 34 46 34 46

18MVAC216 557280 6881822 2 15 30 15 30

18MVAC217 557281 6881662 5 18 37 33 41

18MVAC218 557283 6881501 5 29 30 29 30

18MVAC219 557285 6882812 13 456 1485 456 1485

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18MVAC220 557283 6883596 54 No Result – Did not reach bedrock

18MVAC221 557285 6883584 73 71 46 566 139

18MVAC222 559180 6883400 14 0 24 27 40

18MVAC223 556270 6883400 29 165 31 173 141

18MVAC224 556154 6883399 37 794 31 794 53

18MVAC225 557650 6885900 6 32 22 64 28

18MVAC226 558020 6885900 4 40 23 40 31

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Appendix- JORC Code, 2012 Edition Table 1

The following table relates to activities undertaken at Great Boulder’s Yamarna project.

Section 1 Sampling Techniques and Data

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

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.

This announcement, and table, reports preliminary

outcomes from airborne Electromagentic Survey

undertaken in March and April 2018, and also an

update of Aircore (AC) drilling at Great Boulder

Resources’ (GBR) Mt Venn project (Yamarna).

As previously reported, recent drilling has been

completed at the project, geological logging is

ongoing and final laboratory assay are yet to be

received.

The aircore (AC) programme included 226 holes

across the Eastern Mafic complex for 5,526m.

Geological logging, supported by handheld XRF was

conducted on AC downhole intervals. Only end of

hole AC samples are being submitted for

laboratory analysis. This update relates to

preliminary field handheld XRF results in lieu of

pending laboratory assay results. Samples were

scanned by the company geologists using a

handheld XRF (Olympus Vanta) for 30 seconds.

While these handheld XRF results are not absolute,

they are considered adequate for the purpose of

identifying geochemical anomalies while final

laboratory results are pending.

The airborne EM survey was carried out at a 150m

line spacing with approximately 3m sample interval

using SkyTEM 312- dB/dt system by SKYTEM

Australia

The sampling techniques used are deemed

appropriate for the style of exploration.

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).

Aircore (AC) drilling using a face sampling blade, or

where AC hammer method used, a face sampling

bit. Maximum hole depth for the AC drilling was

123m.

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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.

Logging of all samples followed established

company procedures which included recording of

qualitative fields to allow discernment of sample

reliability. This included (but was not limited to)

recording: sample condition, sample recovery,

sample method.

While no issues relating to sample recovery have

been note, final recovery assessment has not been

completed.

No quantitative analysis of samples weights,

sample condition or recovery has been

undertaken.

No quantitative twinned drilling analysis has been

undertaken at the project.

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.

Geological logging of samples followed established

company and industry common procedures.

Qualitative logging of samples included (but was

not limited to) lithology, mineralogy, alteration and

weathering. Logging was supported by the use of

a handheld XRF.

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.

Aircore (AC) drill chips were collected as 4m

composite samples from bulk piles laid out next to

the drillhole collar using a handheld scoop. Only

end of hole samples are submitted for laboratory

analysis. Entire samples were pulverised. No field

duplicates were taken.

Samples were scanned by the company geologists

using a handheld XRF (Olympus Vanta) for 30

seconds. While these handheld XRF results are not

absolute, they are considered adequate for the

purpose of identifying geochemical anomalies

while final results laboratory results are pending.

All samples were submitted to ALS Minerals

(Kalgoorlie) for analyses. The sample preparation

included:

Samples were weighed, crushed (such

that a minimum of 70% pass 2mm) and

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• Whether sample sizes are appropriate

to the grain size of the material being

sampled.

pulverised (such that a minimum of 85%

pass 75um) as per ALS standards.

A 4 acid digest (HNO3-HBr-HF-HCl) and

ICP-AES (ALS method; MS-ICP61g) was

used for 33 multi-elements. This also

included Co, Cu, Ni, Zn. Note: ME-MS61g

uses HBr in lieu of HClO3 (used in ME-

MS61 4 acid digest). This change relates to

improving resolution of sulphur values in

Mt Venn mineralsation.

For elements that reported over range,

ALS used ore grade 4 acid digest and ICP-

AES methods; (nickel) Ni-OG62, (copper)

Cu-OG62.

Sulphur over range used ALS method S-

IR08 (Leco Sulphur analyzer).

Iron over range used ALS method Fe-ICP81 (Sodium Peroxide Fusion).

Sample collection, size and analytical methods are

deemed appropriate for the style of exploration.

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.

• Final laboratory assay results are pending.

Samples were scanned by the company geologists

using a handheld XRF (Olympus Vanta) for 30

seconds (15 sec. Beam 1, 15 sec. Beam 2). No

blanks or standards were used to calibrate the

handheld XRF. While these handheld XRF results

are not absolute, they are considered adequate for

the purpose of identifying geochemical anomalies

while final results laboratory results are pending.

Drilling has been completed and geological logging

is still being finalized. No final assay results have

yet been received.

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,

No verification of sampling and assaying has been

undertaken in this exploration programme.

No final assay results have yet been received.

Great Boulder has strict procedures for data

capture, flow and data storage, and validation.

ASX Announcement

30 April, 2018

16

data storage (physical and electronic)

protocols.

• Discuss any adjustment to 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.

• Drill collars were set out using a hand held GPS and

final collar were collected using a handheld GPS.

• Downhole surveys were completed by survey

contractors using a north-seeking gyroscope.

Holes without downhole survey use planned or

compass bearing/dip measurements for survey

control.

• The MGA94 UTM zone 51 coordinate system was

used for all undertakings.

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.

The spacing and location of the majority of the

drilling in the projects is, by the nature of early

exploration, variable.

The spacing and location of data is currently only

being considered for exploration purposes.

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 was nominally perpendicular to regional

mineralisation trends where interpreted and

practical. True width and orientation of

intersected mineralisation is currently unknown.

A list of the drillholes and orientations are

reported with significant intercepts is provided as

an appended table.

The spacing and location of the data is currently

only being considered for exploration purposes.

Sample

security

• The measures taken to ensure sample

security.

Great Boulder has strict chain of custody

procedures that are adhered to for drill samples.

All sample bags are pre-printed and pre-numbered.

Sample bags are placed in a polyweave bags (up to

5 samples) and closed with a zip tie such that no

sample material can spill out and no one can

tamper with the sample once it leaves the

company’s custody.

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30 April, 2018

17

Audits or

reviews

• The results of any audits or reviews of

sampling techniques and data.

None completed.

Section 2 Reporting of Exploration Results

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

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

license to operate in the area.

Great Boulder Resource Ltd (GBR) is comprised

of several projects with associated tenements;

Yamarna tenements and details;

Exploration licences E38/2685, E38/2952,

E38/2953, E38/5957, E38/2958, E38/2320 and

prospecting licence P38/4178 where,

GBR has executed a JV agreement to earn 75%

interest through exploration expenditure of

$2,000,000 AUD over five years. Following

satisfaction of the minimum expenditure

commitment by GBR, EGMC (current tenement

owner) will have the right to contribute to

expenditure in the project at its 25% interest

level or choose to convert to a 2% Net Smelter

Royalty (NSR). Should EGMC choose to convert

its remaining interest into a 2% NSR, then GBR

will have a 100% interest in the project.

Exploration

done by other

parties

• Acknowledgment and appraisal of

exploration by other parties.

Previous explorers included:

1990’s. Kilkenny Gold NL completed

wide-spaced, shallow, RAB drilling

over a limited area. Gold assay only.

2008. Elecktra Mines Ltd (now Gold

Road Resources Ltd) completed two

shallow RC holes targeting extension

to Mt Venn igneous complex. XRF

analysis only, no geochemical analysis

completed.

2011. Crusader Resources Ltd

completed broad-spaced aircore

drilling targeting extensions to

Thatcher’s Soak uranium

mineralisation. XRF anlaysis only, no

geochemical analysis completed.

In late 2015 Gold Road drilled and

assayed an RC drill hole on the edge of

an EM anomaly identified from an

airborne XTEM survey, identifying

copper-nickel-cobalt mineralisation.

ASX Announcement

30 April, 2018

18

Geology • Deposit type, geological setting and

style of mineralisation.

Great Boulder’s Yamarna Project hosts the

southern extension of the Mt Venn igneous

complex. This complex is immediately west of

the Yamarna greenstone belt.

The mineralisation encountered in the Mt Venn

drilling suggests that sulphide mineralisation is

prominent along a EM conductor trend, and

shows a highly sulphur-saturated system within

metamorphosed dolerite and gabbro sequence.

Visual logging of sulphide mineralogy shows

pyrrhotite dominant with chalcopyrite.

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.

A complete list of the reported significant

results from Great Boulder’s drilling is provided

in the body of the report.

A list of the drillhole coordinates and metrics

are provided as an appended table.

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

No weight averaging techniques, aggregation

methods or grade truncations were applied to

these exploration results.

No metal equivalents are used.

ASX Announcement

30 April, 2018

19

such aggregations should be shown

in detail.

• The assumptions used for any

reporting of metal equivalent values

should be clearly stated.

Relationship

between

mineralisatio

n 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 orientation of structures and

mineralisation is not known with certainty but

drilling was conducted using appropriate

orientations for interpreted mineralisation.

True width and orientation of intersected

mineralisation is currently unknown.

A list of the drillholes and orientations are

reported with significant intercepts is provided

as an appended table.

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 announcement.

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.

It is not practical to report all exploration

results. Low or non-material grades have not

been reported.

All drill hole locations are reported and a table

of significant intervals is provided in the

announcement.

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.

In late 2015 Gold Road drilled and assayed an

RC drill hole on the edge of an EM anomaly

identified from an airborne XTEM survey,

identifying copper-nickel-cobalt mineralisation.

Great Boulder subsequently re-assayed the

hole and confirmed primary bedrock sulphide

mineralisation, with peak assay results of 1.7%

Cu, 0.2% Ni, 528ppm Co (over 1m intervals)

over two distinct lenses.

Great Boulder completed a ground based

moving loop EM survey in September 2017 and

reported extensive strong EM conductors and

co-incident copper-nickel mineralisation from

ASX Announcement

30 April, 2018

20

aircore geochemistry (refer to announcement

dated 5 October 2017).

Great Boulder has also recently undertaken RC

and DD exploratory drilling with down hole EM

surveys.

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.

Potential work across the project may include

detailed additional geological mapping and

surface sampling, additional geophysical

surveys (either surface or downhole), and

potentially additional confirmatory or

exploratory drilling.

Documents

Highly successful EM survey identifies multiple conductors