technical report on the nechalacho deposit, thor lake project ...

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cross-cutting relationships and they are in fact believed by Avalon’s geologists to be timeequivalent. It is now believed that the only real differences between the Thor Lake Syenite and Grace Lake Granite are their varying quartz contents and the degree of silica saturation. In fact, the two sub-units likely reflect a single early intrusive magma pulse which preceded a second related pulse of nepheline sodalite-bearing peralkaline magma. Until 2010, the hydrothermally altered apical portion of this nepheline syenite was believed to be exposed only under and between Thor and Long Lakes. Previously it was described as altered Thor Lake Syenite. Now the nepheline syenite unit has been encountered in drilling north of Thor Lake, and under Cressy Lake, thus establishing that it is more extensive than originally believed. Drilling of the Nechalacho deposit has also shown that the same nepheline-sodalite peralkaline syenite that underlies the Thor Lake Syenite is, in fact, a distinct intrusion. The nepheline syenite is now informally referred to as the “Nechalacho syenite”. Recent age-dating of the BLC supports the view that all of the intrusions are related since the main eastern and western intrusive centres have comparable ages. The Hearne Channel Granite has been dated at 2,175 +/-5 million years while the Whiteman Lake Syenite is dated at 2,185 +/-5 million years (Bowring et al, 1984) and the Grace Lake Granite is dated at 2,176+/- 1.3 million years (Sinclair and Richardson, 1994). Henderson (1985) <strong>report</strong>s that small dioritic plugs, which have been assigned to the Compton Lake Intrusive Suite, cross-cut the Grace Lake Granite. As well, diabase dykes of the 1,200 million year old Mackenzie swarm and the 2,000 million year old Hearne dyke swarm cut most of the members of the BLC. Most of the Thor Lake Property is underlain by the Thor Lake Syenite and Nechalacho syenite within the central part of the Grace Lake Granite. The T-Zone deposits cross-cut both rock types whereas the Nechalacho deposit is confined to the area of the hosted in the underlying Nechalacho nepheline syenite. The Grace Lake Granite is a coarse-grained, massive, equigranular, riebeckite-perthite granite with about 25% interstitial quartz. Near the contact between the Grace Lake Granite with the Thor Lake Syenite the two units are texturally similar and the contact appears to be gradational over a few metres. Because of their textural similarity and gradational contact relations, Davidson suggested that both rock types are derived from the same magma. The Thor Lake Syenite is completely enclosed by the Grace Lake Granite. The most distinctive sub-unit is a fayalite-pyroxene mafic syenite which locally has a steep dip and is located close to the margin of the main amphibole syenite and the Grace Lake Granite. It forms a distinct semicircular ridge, locally termed the rim syenite, which can be traced for a distance of about eight kilometres and has the appearance of a ring dyke, most prominent on the east side of the Thor Lake body. The rim syenite is clearly identifiable on the airborne magnetic map. Technical Report 43-101 – March 13, 2011 Page 7-3 Prepared by Avalon Rare Metals Inc.
The nepheline-sodalite syenite hosting the Nechalacho deposit, here termed the Nechalacho nepheline sodalite syenite, has the following key distinctive features which contrast it to the Thor Lake Syenite and Grace Lake Granite: • It has a distinct chemical composition with under-saturation in quartz as shown by the presence of nepheline and sodalite as primary rock-forming minerals. • It displays cumulate layering. • It contains agpaitic zircon-silicates (including eudialyte). • It is the host to the Nechalacho zirconium-niobium-tantalum-rare earth element mineralization. The Nechalacho Syenite is only exposed at surface in a small portion of the Thor Lake Syenite between Long and Thor Lakes. It is believed that the Nechalacho Syenite dips underneath the Thor Lake syenite in all directions. This is supported by drilling north of Thor Lake, within and close to Cressy Lake. Also, the Nechalacho mineralization occurs in the top, or apex, of the Nechalacho nepheline syenite. The Nechalacho nepheline sodalite syenite consists of a layered series of rocks with increasing peralkaline characteristics at depth. A consistent, downward progression is noted from the hanging wall sodalite cumulates, through the coarse-grained or pegmatitic nepheline aegirine syenites (which are locally enriched in zircon-silicates), to foyaitic syenite within a broad zone of altered “pseudomorphs-after-eudialyte” cumulates (referred to as the Basal Zone). This upper sequence is also intensely altered by various Na and Fe hydrothermal fluids. Pre-existing zircon-silicates are completely replaced by zircon, allanite, bastnaesite, fergusonite and other minerals. Beneath the Basal Zone cumulates, mineralization decreases rapidly, but alteration decreases more gradually, with relict primary mineralogy and textures increasingly preserved. Aegirine and nepheline-bearing syenites and foyaitic syenites progress downward to sodalite foyaites and naujaite. Drilling has not extended beyond this sodalite lithology to date. Minerals related to agpaitic magmatism identified from this lower unaltered sequence include eudialyte, catapleite, analcime, and possibly mosandrite. REGIONAL STRUCTURES The BLC was emplaced in a setting that was initially extensional with a triple junction rift consisting of structures oriented at azimuths of 060 to 070 degrees, 040 degrees, and 330 degrees. These structures are readily seen on large-scale topographic and magnetic maps but their presence can be detected at the outcrop scale and within the distribution of the structurally influenced mineralized zones (R-, S-, and T-zones). The 060 to 070 degrees and the 040 degrees structures represent orientations of the failed “East Arm Aulacogen” now occupied by the Hearne Channel in the vicinity of the Nechalacho deposit. The presence of younger, Aphebian-age, metasedimentary and metavolcanic rocks of the Great Slave Supergroup to the Technical Report 43-101 – March 13, 2011 Page 7-4 Prepared by Avalon Rare Metals Inc.
Page 1 and 2: TECHNICAL REPORT ON THE NECHALACHO
Page 3 and 4: TABLE OF CONTENTS 1. SUMMARY ......
Page 5 and 6: QUALITY ASSURANCE / QUALITY CONTROL
Page 7 and 8: Warehouse..........................
Page 9 and 10: LIST OF TABLES Table 1-1 Summary of
Page 11 and 12: Table 18-9 Mine Ventilation Quantit
Page 13 and 14: Table 18-54 Table 18-55 Pine Point
Page 15 and 16: LIST OF APPENDICES APPENDIX A Block
Page 17 and 18: Table 1-1 Summary of Mineral Resour
Page 19 and 20: Royalties. The net revenue generate
Page 21 and 22: • The products will be shipped in
Page 23 and 24: • Income taxes and NWT mining roy
Page 25 and 26: 2. INTRODUCTION This report
Page 27 and 28: Figure 2-2 Project Sites, Thor Lake
Page 29 and 30: Table 2-1 Rare Earth Element Data A
Page 31 and 32: LIST OF ABBREVIATIONS Units of meas
Page 33 and 34: 4. PROPERTY DESCRIPTION AND LOCATIO
Page 35 and 36: The mining leases have a 21-year li
Page 37 and 38: 5. ACCESSIBILITY, CLIMATE, LOCAL RE
Page 39 and 40: Fort Resolution is located on the s
Page 41 and 42: producing a tantalum concentrate, b
Page 43: Figure 7-2 Detailed Deposit Geology
Page 47 and 48: LATE TECTONIC FAULTS Faults are pre
Page 49 and 50: 8. DEPOSIT TYPES The mineral deposi
Page 51 and 52: The Ore (Nechalacho) Nepheline Soda
Page 53 and 54: from section to section - this may
Page 55 and 56: Table 9-1 Average Percent of Ore Mi
Page 57 and 58: The Nechalacho deposit alteration s
Page 59 and 60: 11. DRILLING Since 1977, diamond dr
Page 61 and 62: Foraco drill rig was added in Febru
Page 63 and 64: CORE LOGGING AND CORE RECOVERY The
Page 65 and 66: A high R 2 (and all regressions had
Page 67 and 68: 12. SAMPLING METHOD AND APPROACH A
Page 69 and 70: such as Illimausaq in Greenland, a
Page 71 and 72: 13. SAMPLE PREPARATION, ANALYSES AN
Page 73 and 74: limited set of elements; however, s
Page 75 and 76: CONCLUSIONS Avalon’s conclusions
Page 77 and 78: Tb and Dy) were routinely monitored
Page 79 and 80: As part of the QA/QC program, Avalo
Page 81 and 82: Table 14-4: Comparison of Niobium,
Page 83 and 84: shows more deviation, with ALS MS81
Page 85 and 86: 16. MINERAL PROCESSING AND METALLUR
Page 87 and 88: In a typical test, for example CCr-
Page 89 and 90: 17. MINERAL RESOURCE AND MINERAL RE
Page 91 and 92: 9. TREO equivalent is estimated by
Page 93 and 94: Table 17-4 Sample Information Avalo
Page 95 and 96:
Figure 17-1 Distribution of REO Com
Page 97 and 98:
Assay Statistics for Upper Zone* *
Page 99 and 100:
CUT-OFF GRADE A previous public res
Page 101 and 102:
underneath for SG measurement purpo
Page 103 and 104:
Figure 17-4 Density Measurements AL
Page 105 and 106:
was equal to 60 m by 60 m by 30 m a
Page 107 and 108:
Table 17-12 Detailed Resource Break
Page 109 and 110:
Table 17-13 Indicated Mineral Resou
Page 111 and 112:
Figure 17-7 Outline of Area of Indi
Page 113 and 114:
The recoveries estimated for the fl
Page 115 and 116:
grades were based upon the grades w
Page 117 and 118:
Figure 18-1 Thor Lake Site Layout T
Page 119 and 120:
Scott Wilson RPA recommends the use
Page 121 and 122:
During discussions with the mine de
Page 123 and 124:
Figure 18-4 Mine Layout Some of the
Page 125 and 126:
Figure 18-5 Mine Development Schema
Page 127 and 128:
Table 18-2 Development Tonnage Brea
Page 129 and 130:
Until the crusher is in place and t
Page 131 and 132:
Lateral Development The access decl
Page 133 and 134:
Equipment will be selected based up
Page 135 and 136:
Table 18-6 Estimated Electrical Loa
Page 137 and 138:
VENTILATION The mine ventilation is
Page 139 and 140:
for closing unused areas and for ch
Page 141 and 142:
Mine Fan Horse Power Using the same
Page 143 and 144:
Paste Fill System A paste fill syst
Page 145 and 146:
Communications Mine communications
Page 147 and 148:
completion of the 30 m to 50 m long
Page 149 and 150:
HEALTH AND SAFETY All crew will be
Page 151 and 152:
The crushing plant is designed for
Page 153 and 154:
Table 18-12 (Cont’d) Principal Pr
Page 155 and 156:
Figure 18-9 Hydrometallurgical Plan
Page 157 and 158:
The Pine Point hydrometallurgical f
Page 159 and 160:
Decant pipeworks have been included
Page 161 and 162:
• Development of pre-feasibility
Page 163 and 164:
Design Basis The pre-feasibility le
Page 165 and 166:
non-woven geotextile) to prevent da
Page 167 and 168:
divert surface drainage away from r
Page 169 and 170:
A high pressure (200 psi) compresse
Page 171 and 172:
Fuel deliveries are assumed to be s
Page 173 and 174:
Mill Supplies The key mill supplies
Page 175 and 176:
Table 18-15 Surface Equipment Fleet
Page 177 and 178:
Figure 18-10 Thor Lake Temporary Ba
Page 179 and 180:
• Together with the unloading log
Page 181 and 182:
it will be necessary to upgrade the
Page 183 and 184:
Table 18-16 Hydrometallurgical Plan
Page 185 and 186:
Table 18-17 Surface Mobile Equipmen
Page 187 and 188:
Rare Earth FOB China* FOB China** P
Page 189 and 190:
• loparite and eudialyte in alkal
Page 191 and 192:
Table 18-18 Rare Earth supply - 200
Page 193 and 194:
Table 18-20 Rare Earth Demand by Ap
Page 195 and 196:
Table 18-22 Proposed New REO Projec
Page 197 and 198:
in China. On this basis, Avalon is
Page 199 and 200:
Determine Prices for Avalon’s Pro
Page 201 and 202:
The balance of niobium supply is co
Page 203 and 204:
epresenting about 18% of total zirc
Page 205 and 206:
Table 18-25 Historic Chinese Export
Page 207 and 208:
Figure 18-16 Tantalum Markets - 200
Page 209 and 210:
the price for tantalum chemicals in
Page 211 and 212:
Surface Hydrology The Thor Lake dra
Page 213 and 214:
seven) have occurred more frequentl
Page 215 and 216:
elative to uranium, the overall eff
Page 217 and 218:
interviews conducted for the nearby
Page 219 and 220:
Wildlife Early science-based wildli
Page 221 and 222:
Other environmental permits/approva
Page 223 and 224:
TAXES The NWT diesel tax has been i
Page 225 and 226:
Table 18-31 Mine Capital Cost Estim
Page 227 and 228:
Table 18-33 Surface Infrastructure
Page 229 and 230:
Table 18-36 Indirect Cost Estimate
Page 231 and 232:
Table 18-37 Contingency Allowance A
Page 233 and 234:
Operating Cost Exclusions The opera
Page 235 and 236:
Table 18-40 Underground Mine Cost S
Page 237 and 238:
Table 18-41 Mine Cost Details Avalo
Page 239 and 240:
Thor Lake Surface The Thor Lake sur
Page 241 and 242:
Table 18-45 Sales and Marketing Cos
Page 243 and 244:
Table 18-47 Rail Car Load Limits Av
Page 245 and 246:
there will be no overhauls in the i
Page 247 and 248:
Other supplies and freight will be
Page 249 and 250:
Table 18-55 Hydrometallurgical Plan
Page 251 and 252:
Table 18-56 Cash Flow Summary Techn
Page 253 and 254:
The sensitivity of the base case 8%
Page 255 and 256:
19. INTERPRETATION AND CONCLUSIONS
Page 257 and 258:
• The Mineral Reserves, which hav
Page 259 and 260:
20. RECOMMENDATIONS The authors of
Page 261 and 262:
21. REFERENCES BCC Research (2009):
Page 263 and 264:
MDN Inc (2010): News Release Melvil
Page 265 and 266:
Wardrop Engineering Inc. (2009): Th
Page 267 and 268:
23. CERTIFICATES OF QUALIFIED PERSO
Page 269 and 270:
CERTIFICATE OF QUALIFIED PERSON I,
Page 271 and 272:
CERTIFICATE OF QUALIFIED PERSON I,
Page 273 and 274:
Section 416000 Section 416100 Secti
Page 275 and 276:
Page 277 and 278:
Page 279 and 280:
Technical Report 43-101 - March 13,
Page 281 and 282:
Page 283 and 284:
Page 285 and 286:
Page 287 and 288:
Page 289:
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