Yangibana Project Exploration

On acquiring the Yangibana Project in 2011, Hastings undertook a review of previous exploration results and identified a significant difference in the rare earths geochemistry between the 12km long, WNW-trending zone between Yangibana North and Kane’s Gossan deposits (subsequently termed the Western Belt) and other deposits at Bald Hill and Fraser’s (subsequently termed the Eastern Belt), Yangibana and Yangibana South.

The Western Belt deposits were found to host rare earths with ratios of between 16-22%Nd2O3:TREO compared to Eastern Belt deposits where ratios of between 34-38%Nd2O3:TREO occur. Yangibana and Yangibana South show even higher ratios of between 43-44%Nd2O3:TREO. Although Western Belt TREO grades were higher than those for the Eastern Belt, it was apparent that, assuming similar metallurgical characteristics, any concentrate produced from the latter sources would have a significantly higher Nd2O3 and Pr6O11 content.

Hastings has completed a number of regional rock chip sampling programmes designed to verify known target areas and to assist with new target identification and characterisation. The figure below shows the results of all rock chip samples with the ratio of Nd2O3+Pr6O11:TREO shown. This diagram clearly shows zonation among the ironstones from high Nd2O3+Pr6O11 through the centre and to the east of the project area (Yangibana, Yangibana South, Bald Hill, Fraser’s), to lower Nd2O3+Pr6O11 in the north (Yangibana West to Kane’s Gossan). Sampling at Auer and Auer North indicates that the ironstone along this north-south trending structure is gradational between high and low Nd2O3+Pr6O11. The Nd2O3+Pr6O11:TREO ratio has been used as an exploration tool to prioritise exploration targets for drill testing.

An airborne HyMap Hyperspectral survey has been flown over the Yangibana Project covering a total area of 115 square kilometres. Processing of this data identified previously unidentified ironstone occurrences utilising unique spectral signatures. Analysis of the resultant datasets proved a useful exploration tool for initial target identification and was instrumental in identification of targets such as Simon’s Find, Auer, Mosander, and Demarcay.

High resolution aerial photography and digital terrain model (DTM) surveying has been undertaken over the majority of the project area. These datasets provide an excellent base for field mapping, target identification and verification. The DTM provides topographic control for all drillholes and resource estimation.

High resolution airborne magnetic and radiometric data was flown over the Yangibana Project. Processing and interpretation completed by Southern Geoscience Consultants identified 108 thorium anomalies, with 22 areas identified as priorities for further exploration. Work continues to assess these exploration targets.

As part of these assessments, detailed interpretation of the area between Auer and Fraser’s deposits identified a major aeromagnetic anomaly of considerable size. The anomaly is considered to represent a magnetite-rich body and magnetite is known to be associated with rare earths in the Yangibana deposits. This target remains to be drill-tested. The interpretation also identified a southerly extension to the Auer deposit that was successfully drill-tested in mid-2018.

Drilling

Hastings has completed eight phases of drilling to date as described below.

Phase 1 drilling was completed during May 2014. The programme consisted of 1,836m of RC drilling in 44 reverse circulation (RC) drillholes, at the Yangibana North prospect. This drilling tested a strike length of approximately 400m of outcropping ironstone and quartz veining with the intention of verifying the earlier results achieved by Hurlston in the late 1980s. Drilling depths ranged from 12-90m, with all drillholes completed intersecting the target ironstone unit, which was confirmed to be dipping shallowly to the south.

Phase 2 drilling was undertaken between August and October of 2014. This drilling tested five Western Belt prospects comprising Yangibana North, Gossan, Lion’s Ear, Hook, Kane’s Gossan, and two Eastern Belt prospects comprising Bald Hill, and Fraser’s. This programme consisted of 6,582m of RC drilling in 116 holes and 171.45m of diamond drilling in 6 RC pre-collared holes with diamond tails, and 3 diamond drillholes from surface.

Phase 3 drilling was undertaken between May-August 2015, and consisted of 249 RC drillholes and 20 diamond drillholes. This programme focused on increasing resources within 100%-held deposits at Bald Hill, Fraser’s, and Yangibana West. Drilling at Yangibana West focused on testing mineralisation directly along strike to the northwest of Yangibana North, where historic drilling by Hurlston had previously identified REE-mineralisation.

Phase 4 drilling was undertaken between May and November 2016, and consisted of 286 RC drillholes and 19 diamond drillholes. This programme focused on 100%-held deposits in the Eastern Belt at Bald Hill and Fraser’s to provide a bulk composite sample for metallurgical testwork and to upgrade the resource status at these deposits.

New targets to the southwest of Fraser’s were tested following rock chip sampling earlier in the year. The Auer deposit received 44 RC holes (2109m), and its northern extension, identified from the Company’s geophysical surveys, received 50 RC holes (3641m). Limited drilling was carried out at new targets Demarcay, Mosander (both in the area to the southwest of Fraser’s).

Phase 5 drilling was undertaken between mid-April and mid-May 2017, and consisted of 63 RC drillholes (4,392m) and 9 diamond drillholes (864.8m). This programme focused on infill and extension of 100%-held deposits in the Eastern Belt at Bald Hill and Fraser’s, and extension at the Western Belt deposits Yangibana West (100%) and Yangibana North (70%).

The drilling established a strong extension to the west of the previous resources at Bald Hill and this became the main target of this programme.

Phase 6 drilling was undertaken between mid-May and mid-August 2017, and consisted of 270 RC drillholes (16,128m) and 29 diamond drillholes (2,247.8m). This programme was focused on identifying additional resources within the 100%-held tenements at Auer and Auer North, and in establishing the first resources at Yangibana and Simon’s Find deposits, each of which hosts mineralisation expected to be of Eastern Belt-style.

Limited drilling tested Terry’s Find and a few additional holes were drilled at Bald Hill. Geotechnical core holes were drilled at Auer, Auer North, Yangibana North and Yangibana West. Twelve holes were drilled into the shallow portion of Yangibana North deposit to provide a representative composite sample for metallurgical testwork.

Phase 7 drilling in late 2017 consisted of 37 RC drillholes (2,728m) mostly to upgrade resources at Auer and Auer North, with two holes at Yangibana West to provide metallurgical samples.

Phase 8 drilling in 2018 comprised 331 RC drillholes (17,156m) and 41 diamond drillholes (2,956.75m). This programme focused on infill drilling at Bald Hill and Fraser’s deposits to provide a new composite sample for further pilot plant testwork, and on infill and extension drilling at Auer and Auer North to establish additional resources and reserves. Nine diamond holes were drilled at Yangibana for geotechnical purposes.

Resource estimations were undertaken after most drilling phases

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