Mineral Resources and Ore Reserves
Mineral Resources and Ore Reserves
Coburn Resource
Mineral Resources
Assay results were received from infill drilling conducted over the first 2-year mining area (refer ASX announcement dated 28 Sept-2021). Drilling returned significant mineral sands intersections, as well as validated broad, continuous and often shallow zones of mineralization. Results bode well for a Mineral Resource upgrade and further optimisation of the first 2-year mine plan; Ore Reserves are expected to be updated prior to first production next year.
The Mineral Resource Estimate was conducted by and under supervision of IHC Robbins’ Greg Jones, a specialist consultant in mineral sands resources and metallurgy (refer to Competent Person statement).
Table 1 below displays the Mineral Resource estimated for the Coburn tenement. The Mineral Resources are classified as Measured, Indicated and Inferred.
Table 1 JORC 2012 Global Mineral Resource Estimate for the Coburn Project, at November 2018
| MINERAL RESOURCE SUMMARY FOR COBURN PROJECT |
| Summary of Mineral Resources(1) |
VHM assemblage(2) |
| Deposit |
Mineral Resource Category |
Tonnage |
In situ THM |
THM |
Ilmenite |
Rutile |
Zircon |
Leucoxene |
Slimes |
Oversize |
| (Mt) |
(Mt) |
(%) |
(%) |
(%) |
(%) |
(%) |
(%) |
(%) |
| |
Measured |
119 |
1.5 |
1.3 |
45 |
5 |
24 |
6 |
3 |
6 |
| |
Indicated |
607 |
7.7 |
1.3 |
48 |
7 |
22 |
5 |
3 |
3 |
| |
Inferred |
880 |
10.4 |
1.2 |
49 |
7 |
21 |
4 |
3 |
1 |
| |
Total(3) |
1606 |
19.6 |
1.2 |
48 |
7 |
22 |
5 |
3 |
2 |
(1) Mineral Resources reported at a cut-off grade of 0.8% THM
(2) Valuable Mineral assemblage is reported as a percentage of in situ THM content
(3) Appropriate rounding applied |
Coburn Mineral Resources - Amy South
Table 2 JORC 2012 Mineral Resource Estimate for the Amy South - Coburn Project, at November 2018
| MINERAL RESOURCE SUMMARY FOR AMY SOUTH COBURN PROJECT |
| Summary of Mineral Resources(1) |
VHM assemblage(2) |
| Deposit |
Mineral Resource Category |
Tonnage |
In situ THM |
THM |
Ilmenite |
Rutile |
Zircon |
Leucoxene |
Slimes |
Oversize |
| (Mt) |
(Mt) |
(%) |
(%) |
(%) |
(%) |
(%) |
(%) |
(%) |
| |
Measured |
119 |
1.5 |
1.3 |
45 |
5 |
24 |
6 |
3 |
6 |
| |
Indicated |
607 |
7.7 |
1.3 |
48 |
7 |
22 |
5 |
3 |
3 |
| |
Inferred |
728 |
8.8 |
1.2 |
49 |
7 |
21 |
4 |
3 |
1 |
| |
Total(3) |
1454 |
18.0 |
1.2 |
48 |
7 |
22 |
5 |
3 |
2 |
(1) Mineral Resources reported at a cut-off grade of 0.8% THM Leucoxene
(2) Valuable Mineral assemblage is reported as a percentage of in situ THM content
(3) Appropriate rounding applied |
The Amy South Resource has a total Mineral Resource of 1454 million tonnes @ 1.2% Total Heavy Minerals (THM) with a valuable mineral assemblage comprising 48% ilmenite, 7% rutile, 5% leucoxene and 22% zircon at a cut-off grade of 0.8% THM. Slime (defined as silt <45µm) content at this cut-off is 3%.
A 30 tonne composite sample from the mineral zones across the Amy South deposit was gathered in July 2018 and has been subjected to a comprehensive phase of LOM confirmatory design and variability studies performed by TZMI’s Allied Mineral Laboratories in Perth.
The mineralised zone for the resource remains open to the east, showing the potential for further resource expansion. In the northern half of the deposit there is scope to improve the confidence of mineralisation from Inferred to Indicated with further infill drilling which in turn may lead to additional delineation of elevated dunal grades.
The Amy North inferred mineral resource is presented in Table 3. No Ore Reserves have been declared over the Amy North mineral resources estimate.
Coburn Mineral Resource – Amy North
Table 3 JORC 2012 Mineral Resource Estimate for the Amy North- Coburn Project, at November 2018
| MINERAL RESOURCE SUMMARY FOR AMY NORTH COBURN PROJECT |
| Summary of Mineral Resources(1) |
VHM assemblage(2) |
| Deposit |
Mineral Resource Category |
Tonnage |
In situ THM |
THM |
Ilmenite |
Rutile |
Zircon |
Leucoxene |
Slimes |
Oversize |
| (Mt) |
(Mt) |
(%) |
(%) |
(%) |
(%) |
(%) |
(%) |
(%) |
| |
Inferred |
151 |
1.6 |
1.1 |
52 |
5 |
16 |
5 |
6 |
2 |
| |
Total(3) |
151 |
1.6 |
1.1 |
52 |
5 |
16 |
5 |
6 |
2 |
(1) Mineral Resources reported at a cut-off grade of 0.8% THM
(2) Valuable Mineral assemblage is reported as a percentage of in situ THM content
(3) Appropriate rounding applied |
The Amy North Resource has a total Mineral Resource of 151 million tonnes @ 1.1% Total Heavy Minerals (THM) with a valuable mineral assemblage comprising 52% ilmenite, 5% rutile, 5% leucoxene and 16% zircon at a cut-off grade of 0.8% THM. Slime (defined as silt <45µm) content at this cut-off is 6%. This total Mineral Resource classified as Inferred and has a mineralogy of 52% ilmenite, 5% rutile, 5% leucoxene and 16% zircon.
Ore Reserves (released 16 April 2019)
- Coburn’s JORC-compliant Ore Reserve is 523Mt grading 1.11% total heavy mineral (THM) for ~5.8Mt of contained heavy mineral; This represents a 70% increase from the previous 2008 Reserve
- The substantial increase is attributed to a combination of improved processing technology, enhanced mining methodology and higher mineral sands prices
- Ore Reserve underpins an initial mine life of 22.5 years at the planned mining rate of 23.4Mtpa
- Low operating costs estimated with ore starting from surface in places, low overburden, low slimes and free digging sand suitable for conventional open pit dry mining
- Measured and Indicated Mineral Resources used as the basis of the Ore Reserves
- Immense potential to further increase project Reserves and mine life, through evaluation and conversion of resources extending north and along strike of the current Ore Reserves
- The Reserve estimate confirms Coburn is one of the largest and most advanced undeveloped zircon-titanium-rich mineral sands deposits in the world.
The Coburn Project Ore Reserve is summarised in Table 1. below.
Table 1 Coburn Project JORC Compliant Ore Reserve April - 2019
| ORE RESERVES SUMMARY FOR COBURN PROJECT |
| Deposit |
Reserve Category |
Ore |
Heavy Mineral |
| (Mt) |
HM (Mt) |
THM (%) |
| Coburn - Amy South |
Proved |
106 |
1.16 |
1.10 |
| Coburn - Amy South |
Probable |
417 |
4.66 |
1.12 |
| |
Total(1) |
523 |
5.83 |
1.11 |
NOTE:
(1) Total may deviate from the arithmetic sum due to rounding |
Table 2 Coburn Life of Mine Product Recoveries Used in Determining the Reserves
| Product |
WCP Recovery (%) |
MSP Recovery (%)2 |
MSP Yield to Saleable Products (%)4 |
| Ilmenite |
86.8 |
96.2 |
102.9 |
| Rutile/HiTi1 |
87.7 |
84.7 |
95.2 |
| Zircon |
98.2 |
99.73 |
98.8 |
NOTE:
(1) Rutile/HiTi product contains rutile leucuxene mineral species
(2) MSP Recoveries are for actual mineral species
(3) MSP Zircon recovery comprises 58.3% into premium zircon and further 41.4% into zircon concentrate as contained zircon.
(4) Actual yields into saleable products higher due to contributions from other mineral. |
Table 3: List of Experts for the Coburn Project Ore Reserve
| Modifying Factor |
Responsible Group |
Responsible Person/s |
| Environmental, land access & community |
AECOM |
Jamie Shaw |
| Geology & Mineral Resource |
IHC Robbins |
Greg Jones |
| Hydrology & water management |
AECOM |
Robert Wallis |
| Tailings management |
Knight Piésold |
Brett Stevenson |
| Geotechnical |
AMC Consultants |
Ruth Stephenson |
| Mining & Ore Reserve |
AMC Consultants |
Adrian Jones |
| Metallurgy |
