SPARTAN RESOURCES LIMITED 57 139 522 900
November 28th 2018
Australian Securities Exchange Limited Via Electronic Lodgement
DALGARANGA GOLD MINE OPERATIONS
AND GILBEYS RESOURCE UPDATE
The project remains Lost Time Incident (LTI) free.
Reconciled gold production for October was 4,898 oz from 176.8kt @ 0.9 g/t, with gold recovered to date in November of 4,894 oz, for a total of 9,792 oz of gold recovered quarter to date (to 26 November), compared to 12,951 ounces for the previous full quarter.
Ore mined for November to date is 176 kt at 0.98 g/t for 5,531 contained ounces.
Daily mining production rate for November has been effected by significant 1 in 20 year rain event on 10 November (52mm in 12 hours) . Estimated impact of the rain event is 130,000 BCM to 150,000 BCM.
Following a partial replacement of SAG mill discharge grates, Ore processed has increased to a rate of 750kt per quarter (3mtpa) and up from 535kt in September Quarter.
Average milling rates at record levels for the last 7 days at 9,450dt per day (~3.2mtpa rate).
Milled ore grade for November to date of 0.83g/t is below expectations following the rain event, and an unplanned shut down to replace split conveyor belts, requiring mill feed to be supplemented from low grade coarse ore stockpile.
Modelling of detailed grade control drilling data to ~65‐70m below surface of major ore source Gilbeys (~85% of feasibility LOM ore supply) has been used to estimate an interim Updated Gilbeys Mineral Resource. The new model provides increased confidence in both short term and long term ore supply, with similar tonnes but at slightly lower grade than pre‐mining resource model.
o Although resulting in a reduction of only ~4.1% of the total Mineral Resource within the planned
LOM Gilbeys pit shell, the greatest impact is in the oxide and transition ore. Within the final design lower tonnes and grade were estimated resulting in a reduction of contained gold of 22,000 ounces.
The ramp up of the project is continuing, however as a result of the impact of rain on the timing of ore releases impacting mill feed grade production for the quarter is revised to 17,000 - 18,000 ounces
A short program of closely spaced RC drilling is planned for December around the high grade intersection at the Tanqueray prospect 2km north of the mill.
Gascoyne Resources Limited ("Gascoyne" or "Company")(ASX:GCY) is pleased to provide an operational update on the Dalgaranga Gold Project.
SAFETY
Pleasingly the project remains Lost Time Incident (LTI) free, since the commencement of construction activities in April 2017 (605 days LTI free to the 26 November2018).
MINING RAMP UP
Mining production rates have reduced since the end of October due to both weather and tighter mining conditions.
A 1 in 20 year rain event (52mm in 12 hrs) effectively closed all three pits for 24 hours and has had a continuing effect over the last two weeks due to saturated ground conditions. An estimated 130,000 to 150,000 BCM of total material movements has been lost from that weather event.
Ore mined for the month to date (26 November) is 176 kt at 0.98 g/t for 5,531 contained ounces.
P.O. Box 1449, West Perth, Western Australia 6872
Level 1, 41-47 Colin Street, West Perth, Western Australia 6005
Telephone +61 8 9481 3434, Facsimile +61 8 9481 0411
Email:admin@gascoyneresources.com.au, Web: www.gascoyneresources.com.au
The rain event on 10th November impacted ore mining particularly in the higher grade central section of the Golden Wings pit and at the southern end of the Gilbeys pit (figure 1).
Mining in Sly Fox has also been delayed this month while testwork is completed on potentially reactive materials in both ore and waste. The testwork has successfully shown we can continue to use the standard emulsion product with blasting commencing again in the coming week.
Figure 1; - Gilbeys pit following rain event on 10 November 2018
The planned accumulation of ROM stocks has been impacted both by the rain event and the resolution of the potential reactive ground in Sly Fox. No substantial ore releases were possible in Golden Wings for a period of 12 days due to the saturated floor conditions. Stockpiles are anticipated to accumulate over the month of December.
DECEMBER QUARTER PRODUCTION TO DATE
In the September Quarterly Report production to date for October (to 25 October) of 3,806 oz was provided on an unreconciled basis. Final October production was 4,898 oz (176,783t @ 0.9 g/t) processed at 95.3% recovery.
For November to date (26 November) production (unreconciled) is ~4,894 oz giving December Quarter to date production of ~9,792 oz.
An unplanned mill shut down occurred in mid November to replace split conveyor belts which required the feed of material from the base of the Coarse Ore Stockpile, which is low grade (0.5g/t) thus lowering the month to date grades.
The ramp up of the project is continuing, however as a result of the above factors impacting mill feed grade, production guidance for the quarter is revised to 17,000 - 18,000 oz.
MILL THROUGHPUT OPTIMISATION
Throughput in November has improved markedly with the installation of 6 hardox grates (of a total of 24 grates installed in the mill) as an interim solution on the 30 October. Mill rates have improved from a daily average of 5,700 dry tonnes per day for the month of October to 7,500 dry tonnes per day for the month of November to date including an average of 9,450 dry tonnes per day for the last week, peaking over 10,000 dry tonnes per day.
Figure 2; Photograph taken 2 weeks after hardox grate installation, with hardox grates essentially clear and the rubber grates almost completely pegged.
As a result, the 36 hour shutdown specifically planned to install the replacement set of grates previously scheduled for installation at the end of November, will be delayed. A shorter, 24 hour, regular plant maintenance shutdown is now planned for mid‐December during which some of the pegged grates will be replaced with the new rubber grates to continue to improve throughput and performance data/knowledge to understand the optimal solution for the current mill feed blend.
Mill throughput for November month to date (26 November) is 203.7 kt at 0.83 g/t and 90% recovery for 4,894 ounces (production for the month to date is unreconciled, reconciliation to occur at month end). This compares with 138kt throughput for the same period in October, a 33% increase month on month.
MODELLING OF GILBEYS GRADE CONTROL DRILLING/ INTERIM UPDATED GILBEYS MINERAL RESOURCE
As reported in the September quarterly the Company engaged Cube Consulting to provide a number of services at Dalgaranga including reviews of grade control, resources and reconciliation. During September and October some 33,000 m of grade control drilling was completed to provide greater confidence in geological and resource/reserve models for near term production. Cube Consulting and resource consultants Ashmore Advisory have worked closely with the Dalgaranga mine staff in preparing an updated grade control model for the Gilbeys Deposit incorporating all grade control results available at the 8 of November.
The updated global Gilbeys Mineral Resource estimate is shown below in Table 1.
Gilbeys Deposit
November 2018 Mineral Resource Estimate (0.5g/t Au Cut-off, Depleted for mining EOM Oct 18)
Type | Measured | Indicated | Inferred | Total |
Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | |
Oxide Transitional Fresh | 0.4 0.5 2.2
| 0.8 0.8 11.8
| 0.3 0.2 10.2
| 1.4 1.6 24.1
|
Total | 3.0 1.5 142,000 | 13.3 1.2 528,000 | 10.8 1.2 426,000 | 27.1 1.3 1,096,000 |
Note:
The Mineral Resource has been compiled under the supervision of Mr. Shaun Searle who is a director of Ashmore Advisory Pty Ltd and a Registered Member of the Australian Institute of Geoscientists. Mr. Searle has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity that he has undertaken to qualify as a Competent Person as defined in the JORC Code.
All Mineral Resources figures reported in the table above represent estimates at 28 November 2018. Mineral Resource estimates are not precise calculations, being dependent on the interpretation of limited information on the location, shape and continuity of the occurrence and on the available sampling results. The totals contained in the above table have been rounded to reflect the relative uncertainty of the estimate. Rounding may cause some computational discrepancies.
Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The Joint Ore Reserves Committee Code - JORC 2012 Edition).
The Gilbeys deposit contains around 85% of total Dalgaranga mining inventory, and although mining has only recently commenced in this pit (173kt mined to end October from 13.2 Mt of reserves) the focus has been on understanding the reasons for variance to resource seen to date, and to improve confidence in the oxide and transition portions of the resource to be mined in the coming months.
The Gilbeys grade control drilling took place initially from natural surface ~ 430 RL and then from the 400 RL predominantly in the major Gilbeys southern pit extension where mining is more advanced, and has provided detailed information on a 10m by 7.5m pattern infilling the approximately 25m by 25m pre‐mining resource drilling. The grade control drilling extends to approximately 360RL (~65‐70m below natural surface), and the re‐modelling extends its influence to around 345RL.
All assays from Gilbeys grade control drilling were re‐wireframed and modelled by Cube using its GCX process . Ashmore has reviewed the Cube wireframes and model, and incorporated the area of grade control drilling into the existing Gilbeys Mineral Resource to derive the interim updated Gilbeys Mineral resource as at 27 November 2018.
For the RL interval from the current Gilbeys pit floor (as at 31 October) to 345RL a comparison is shown below in Table 2 between the new resource model based on detailed grade control drilling, and the previous 2017 pre‐mining resource model (both are undiluted, and adjusted for depletion by mining to date);
Table 2‐ Comparison 2017 and 2018 Mineral Resource above 345RL (area of detailed grade control drilling)
Gilbeys Deposit - Grade Control Area of Influence
November 2018 Mineral Resource Estimate Above Final Design (0.5g/t Au Cut-off, Depleted for mining EOM Oct 18)
Type | Measured | Indicated | Inferred | Total |
Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | |
Oxide Transitional Fresh | 0.4 0.3 0.01 1.4 16,000 1.8 16,000 2.3 1,000 | 0.7 0.4 0.2 1.4 29,000
| 0.1 0.1 0.03 1.3 4,000 1.3 4,000 1.7 1,000 | 1.1 0.8 0.2 1.4 50,000 1.5 39,000 1.5 9,000 |
Total | 0.7 1.6 33,000 | 1.3 1.3 55,000 | 0.2 1.3 10,000 | 2.2 1.4 98,000 |
Gilbeys Deposit - Grade Control Area of Influence
March 2017 Mineral Resource Estimate Above Final Design (0.5g/t Au Cut-off, Depleted for mining EOM Oct 18)
Type | Measured | Indicated | Inferred | Total |
Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | |
Oxide Transitional Fresh | 0.2 0.2 0.01 1.6 8,000 2.4 18,000 2.6 1,000 | 0.8 0.5 0.2
| 0.3 0.1 0.003
| 1.2 0.9 0.2 1.5 61,000 1.7 48,000 1.6 11,000 |
Total | 0.4 2.1 27,000 | 1.5 1.5 72,000 | 0.4 1.5 21,000 | 2.3 1.6 120,000 |
Table notes as above.
As foreshadowed in the September Quarterly the grade control data has largely confirmed the original interpretations at Gilbeys, with a minor reduction in tonnes observed, however the infill drilling has resulted in a reduction in grade of ~0.2g/t gold in the upper sections of the deposit. From the preliminary analysis completed by Cube and Ashmore, it would appear that the losses are largely confined to the oxide and transition zones above the 345 RL with the top of fresh rock boundary modelled at around 355RL in most of the area of grade control drilling. The changes in grade are greatest in the near surface above RL 395, in the area of very strong weathering where the Company has previously reported (September Quarterly) irregular grade depletion and tonnage loss from mining to date both at Golden Wings and Gilbeys. The grade variation between pre‐mining resource model and detailed grade control model lessens with increasing depth.
A comparison of the updated 2018 Gilbeys Mineral Resource model and the 2017 Mineral Resource within the overall life of mine Gilbeys planned pit design, is shown below in Table 3, again on an undiluted basis and depleted for mining to date,
Table 3‐Comparison 2017 and 2018 Mineral Resource -Gilbeys below 31 October surface and within planned pit (undiluted)
Gilbeys Deposit
November 2018 Mineral Resource Estimate Above Final Design (0.5g/t Au Cut-off, Depleted for mining EOM Oct 18)
Type | Measured | Indicated | Inferred | Total |
Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | |
Oxide Transitional Fresh | 0.4 0.5 2.1
| 0.7 0.6 8.1
| 0.1 0.1 0.2 1.3 4,000 1.3 5,000 1.5 11,000 | 1.1 1.2 10.5 1.4 50,000 1.5 56,000 1.3 436,000 |
Total | 3.0 1.4 137,000 | 9.4 1.3 385,000 | 0.4 1.4 20,000 | 12.8 1.3 542,000 |
Gilbeys Deposit
March 2017 Mineral Resource Estimate Above Final Design (0.5g/t Au Cut-off, Depleted for mining EOM Oct 18)
Type | Measured | Indicated | Inferred | Total |
Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | Tonnes MtAu g/tAu Ounces | |
Oxide Transitional Fresh | 0.2 0.4 2.1 1.6 8,000 2.1 29,000 1.4 93,000 | 0.8 0.6 8.2
| 0.3 0.1 0.2
| 1.2 1.2 10.5 1.5 61,000 1.7 64,000 1.3 438,000 |
Total | 2.7 1.5 131,000 | 9.6 1.3 402,000 | 0.7 1.4 31,000 | 13.0 1.4 564,000 |
Table notes as above.
The overall impact of the revision of the model based on the detailed grade control drilling on the total in‐pit Mineral Resource at Gilbeys is a small reduction in tonnes, and a 0.04g/t (rounded in table above) reduction in grade resulting in a reduction in ounces of 4.1 %.
The Gilbeys deposit has significant available geological information, and data on the historical pit production and reconciliation. A comparison of the historical resource and grade control data was also performed by Cube for the lowest levels of the historical Gilbeys pit to test reconciliation in fresh ore, which indicated that there is reasonable expectation that the trend of grade reduction indicated by Gascoyne's grade control drilling in the oxide and transition zones may not continue into fresh rock.
Ashmore's estimate of the updated Gilbeys Mineral Resource at 27 November 2018 is based on a review of the grade control model provided by Cube and its incorporation into the 2017 Gilbeys Mineral resource Estimate
The Company will now use the updated resource model for mine scheduling.
Listing Rule 5.8.1
Pursuant to ASX listing rule 5.8.1, and in addition to the information contained in Appendix 3, the Company provides the following in respect of the interim 2018 Gilbeys Mineral Resource update:
Gilbeys Deposit Geology and Geological interpretation;
The Gilbeys gold deposit forms part of the Dalgaranga Gold Project and is located in the Archaean aged Dalgaranga Greenstone Belt 70km northwest of Mt Magnet in the Murchison Province of Western Australia.
The northeast trending belt consists of basalts, sediments (mainly black shales) and felsic volcanic rocks intruded by large gabbro complexes and post tectonic granites. The Gilbeys deposit is located on the western limb of a southerly
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Gascoyne Resources Ltd. published this content on 28 November 2018 and is solely responsible for the information contained herein. Distributed by Public, unedited and unaltered, on 28 November 2018 01:15:03 UTC
