Significant New Zone of Bornite Gold-Rich Porphyry Mineralisation
HIGHLIGHTS
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- KHDDH488 discovers a significant new zone of high-grade mineralisation outside the current open pit resource returning:
- 352m @ 0.41% Cu & 0.58g/t Au (0.78% eCu or 1.22g/t eAu) from 448m,
including 102m @ 1.00% Cu and 1.67g/t Au (2.06% eCu or 3.23g/t eAu) from 572m,
including 78m @ 1.14% Cu and 2.06g/t Au (2.45% eCu or 3.85g/t eAu) from 594m,
including 14m @ 1.51% Cu and 3.36g/t Au (3.66% eCu or 5.73g/t eAu) from 622m
and 10m @ 2.24% Cu and 5.28g/t Au (5.60% eCu or 8.78g/t eAu) from 658m
- KHDDH488 extends known mineralisation in the central portion of the Stockwork Hill Deposit approximately 200 metres to the southeast and 100 metres east of KHDDH419;
- The discovery has revealed a transition to a zone of higher temperature sulphide mineral assemblages, i.e. bornite, in the intrusive root to the deposit;
- New results are expected to enhance the mining economics significantly;
- Follow up drilling is underway to further quantify the positive impacts;
- Remaining assay results from KHDDH488 expected in the coming weeks.
TORONTO, Feb. 28, 2019 - Xanadu Mines Ltd. (ASX: XAM, TSX: XAM) (“Xanadu” or “the Company”) is pleased to report partial assay results for diamond drill hole KHDDH488 which has returned a thick intercept of high-grade copper and gold mineralisation. The latest drilling results have confirmed a transition to higher temperature sulphide mineral assemblages such as bornite in the intrusive root to the deposit, with a significant increase in the gold-to-copper ratio associated with increasing bornite. The high-grade bornite occurs within a highly mineralised quartz monzodiorite intrusion that appears to be one of the primary sources of mineralisation for the entire Kharmagtai deposit, which is located in the south Gobi region of Mongolia (Figures 1 and 2). The current drilling is targeting high-grade mineralisation associated with the causative copper and gold porphyry at depth.
Xanadu’s Managing Director & Chief Executive Officer, Dr Andrew Stewart, said “After two and a half years of intensive exploration, it is remarkable that our drilling has intersected a significant new zone of bornite-rich porphyry which has produced one of the best intersections of copper and gold mineralisation encountered on the property. Like most classic gold-rich porphyry systems, the target is the bornite zone which correlates with high copper values, but significantly also a higher gold-to-copper ratio.
Hole KHDDH488 has successfully demonstrated the existence of high-grade mineralisation along strike and at depth of the current open pit resource. This represents an exciting new development for the project following the release of an interim open pit resource last year and we are particularly excited with the new results from this hole which are expanding a new zone of bornite porphyry mineralisation. We are very confident these results will provide the basis for a significant increase in the size and grade of the overall Kharmagtai deposit and have a positive impact on ongoing economic studies.”
EXTENSION TO THE STOCKWORK HILL DEPOSIT DESCOVERED
Drilling is targeting mineralisation below chalcopyrite‐gold mineralisation to test for a higher-grade bornite core in the root zones of the causative porphyry intrusion. High-grade mineralisation may manifest as bornite‐gold‐cemented breccia or as bornite‐gold stockwork mineralisation in the causative intrusive.
KHDDH488 has returned:
352m @ 0.41% Cu & 0.58g/t Au (0.78% eCu or 1.22g/t eAu) from 448m,
including 102m @ 1.00% Cu and 1.67g/t Au (2.06% eCu or 3.23g/t eAu) from 572m,
including 78m @ 1.14% Cu and 2.06g/t Au (2.45% eCu or 3.85g/t eAu) from 594m,
including 14m @ 1.51% Cu and 3.36g/t Au (3.66% eCu or 5.73g/t eAu) from 622m
and 10m @ 2.24% Cu and 5.28g/t Au (5.60% eCu or 8.78g/t eAu) from 658m.
Assays for the remaining 400 metres of the drill hole are expected in the coming weeks. A wedge hole KHDDH488a as been initiated to test up-dip of this intercept and define the orientation of the high-grade bornite mineralisation.
KHDDH488 has extended the Stockwork Hill deposit a minimum of 200 metres beyond the southern limit of the open cut resource estimate that was prepared by CSA in October 2018 and 100 metres to the east of the drill intercept in KHDDH419 (see Xanadu’s ASX announcement – 26 September 2017; Figure 2) which intersected:
KHDDH419 − 294m @ 0.47% Cu & 0.85g/t Au (1.01% eCu or 1.59g/t eAu) from 466m,
Including 86m @ 0.78% Cu and 1.91g/t Au (2.0% eCu or 3.14g/t eAu) from 558m.
The high-grade bornite zone as currently drilled, appears to be the tip of a wedge of mineralisation that could broaden significantly at depth. Drilling will focus on expanding this wedge of mineralisation in the coming months.
Photos accompanying this announcement are available at:
http://www.globenewswire.com/NewsRoom/AttachmentNg/0ad0bb84-1d31-4279-b935-59edbd9f965e
http://www.globenewswire.com/NewsRoom/AttachmentNg/adf5e645-33c4-4241-8727-3593af2e0027
http://www.globenewswire.com/NewsRoom/AttachmentNg/76a6ccdd-f786-4dc2-8cd0-92f8d11200bb
http://www.globenewswire.com/NewsRoom/AttachmentNg/647dda6a-c954-46f8-8955-01b074f36b35
COMPETENT-QUALIFIED PERSON STATEMENT
The information in this announcement that relates to exploration results is based on information compiled by Dr Andrew Stewart who is responsible for the exploration data, comments on exploration target sizes, QA/QC and geological interpretation and information. Dr Stewart, who is an employee of Xanadu and is a Member of the Australasian Institute of Geoscientists, has sufficient experience relevant to the style of mineralisation and type of deposit under consideration and to the activity he is undertaking to qualify as the “Competent Person” as defined in the 2012 Edition of the “Australasian Code for Reporting Exploration Results, Mineral Resources and Ore Reserves” and the National Instrument 43-101. Dr Stewart consents to the inclusion in the report of the matters based on this information in the form and context in which it appears.
COPPER EQUIVALENT CALCULATIONS
The copper equivalent (CuEq) calculation represents the total metal value for each metal, multiplied by the conversion factor, summed and expressed in equivalent copper percentage. Grades have not been adjusted for metallurgical or refining recoveries and the copper equivalent grades are of an exploration nature only and intended for summarising grade. The copper equivalent calculation is intended as an indicative value only. The following copper equivalent conversion factors and long-term price assumptions have been adopted: Copper Equivalent Formula (CuEq) = Cu% + (Au (ppm) x 0.6378). Based on a copper price of $2.60/lb and a gold price of $1,300/oz.
TABLE 1: Currently returned assay intercepts for Stockwork Hill
Hole ID | Prospect | From (m) | To (m) | Interval (m) | Au (g/t) | Cu (%) | CuEq (%) | AuEq (g/t) |
KHDDH488 | Stockwork Hill | 3.4 | 29 | 25.6 | 0.06 | 0.09 | 0.13 | 0.20 |
and | 39 | 103 | 64 | 0.14 | 0.10 | 0.19 | 0.29 | |
including | 53 | 59 | 6 | 0.26 | 0.25 | 0.42 | 0.66 | |
and | 117 | 148 | 31 | 0.10 | 0.24 | 0.30 | 0.47 | |
including | 134 | 140 | 6 | 0.24 | 0.57 | 0.72 | 1.13 | |
and | 170 | 372.1 | 202.1 | 0.22 | 0.21 | 0.35 | 0.55 | |
including | 178 | 191.2 | 13.2 | 0.27 | 0.35 | 0.52 | 0.82 | |
including | 201 | 207 | 6 | 0.28 | 0.22 | 0.40 | 0.62 | |
including | 227 | 251 | 24 | 0.27 | 0.21 | 0.39 | 0.60 | |
including | 229 | 241 | 12 | 0.37 | 0.25 | 0.49 | 0.76 | |
including | 261 | 345 | 84 | 0.28 | 0.26 | 0.43 | 0.68 | |
including | 263 | 271 | 8 | 0.14 | 0.45 | 0.54 | 0.85 | |
including | 321 | 331 | 10 | 0.53 | 0.31 | 0.65 | 1.01 | |
including | 355 | 369 | 14 | 0.44 | 0.27 | 0.55 | 0.86 | |
including | 357 | 363 | 6 | 0.66 | 0.35 | 0.77 | 1.21 | |
and | 394 | 400 | 6 | 0.03 | 0.11 | 0.13 | 0.21 | |
and | 412 | 426 | 14 | 0.04 | 0.10 | 0.13 | 0.20 | |
and | 448 | 800 | 352 | 0.58 | 0.41 | 0.78 | 1.22 | |
including | 530 | 540 | 10 | 0.09 | 0.22 | 0.28 | 0.43 | |
including | 550 | 676 | 126 | 1.39 | 0.88 | 1.77 | 2.77 | |
including | 572 | 674 | 102 | 1.67 | 1.00 | 2.06 | 3.23 | |
including | 572 | 584 | 12 | 0.38 | 0.59 | 0.83 | 1.30 | |
including | 594 | 672 | 78 | 2.06 | 1.14 | 2.45 | 3.85 | |
including | 690 | 736 | 46 | 0.31 | 0.24 | 0.44 | 0.69 | |
including | 710 | 732 | 22 | 0.26 | 0.25 | 0.41 | 0.65 | |
including | 748 | 758 | 10 | 0.25 | 0.25 | 0.41 | 0.64 | |
including | 782 | 798.6 | 16.6 | 0.18 | 0.12 | 0.24 | 0.38 | |
and | 883 | 1214.4 | Assays pending |
Intercepts are weighted averages to ensure different sample lengths do not skew the results. There is insufficient information to understand true widths at this stage. Due to the size of the system and current ambiguity around orientation of the drill hole relative to minor diluting intrusives, a larger than normal internal dilution of 9m has been used to calculate a geologically relevant intercept. Cut-off grades and maximum dilution details are included in the tabulated intercepts for clarity.
TABLE 2: Drill hole collar location
Hole ID | Prospect | East | North | RL | Azimuth (°) | Inc (°) | Depth (m) |
KHDDH488 | Stockwork Hill | 592741 | 4877800 | 1284 | 180 | -73 | 901.0 |
For further information, please contact:
Andrew Stewart
Managing Director & Chief Executive Officer
T: +612 8280 7497
M: +976 9999 9211
Andrew.stewart@xanadumines.com
www.xanadumines.com
APPENDIX 1: KHARMAGTAI TABLE 1 (JORC 2012)
1.1 JORC TABLE 1 – SECTION 4 ESTIMATION AND REPORTING OF ORE RESERVES
Set out below is Section 1 and Section 2 of Table 1 under the JORC Code, 2012 Edition for the Kharmagtai project. Data provided by Xanadu. This Table 1 updates the JORC Table 1 disclosure dated 31 July 2018.
1.2 JORC TABLE 1 - SECTION 1 - SAMPLING TECHNIQUES AND DATA
Criteria | JORC Code explanation | Commentary |
Sampling techniques |
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Drilling techniques |
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Drill sample recovery |
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Logging |
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Sub-sampling techniques and sample preparation |
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Quality of assay data and laboratory tests |
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Verification of sampling and assaying |
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Location of data points |
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Data spacing and distribution |
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Orientation of data in relation to geological structure |
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Sample security |
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Audits or reviews |
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1.3 JORC TABLE 1 - SECTION 2 - REPORTING OF EXPLORATION RESULTS
Criteria | JORC Code explanation | Commentary | |||||||||
Mineral tenement and land tenure status |
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Exploration done by other parties |
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Geology |
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Drill hole Information |
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Timing | RC Holes | Metre | DDH Holes | Metre | RC & DDH | Metre | Trench | Metre | |||
Drilling <2015 | 155 | 24553 | 252 | 88511 | 0 | 0 | 106 | 39774 | |||
Drilling >2015 | 68 | 13107 | 116 | 57876 | 22 | 5323 | 17 | 5618 | |||
Total | 223 | 37660 | 368 | 146387 | 22 | 5323 | 123 | 45392 | |||
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Data aggregation methods |
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Relationship between mineralisation widths and intercept lengths |
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Diagrams |
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Balanced reporting |
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Other substantive exploration data |
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Further work |
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1.4 JORC TABLE 1 – SECTION 3 ESTIMATION AND REPORTING OF MINERAL RESOURCES
Criteria | JORC Code explanation | Commentary | |
Database integrity |
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Site visits |
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Geological interpretation |
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Dimensions |
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Estimation and modelling techniques |
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Moisture |
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Cut-off parameters |
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Mining factors or assumptions |
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Metallurgical factors or assumptions |
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Environmental factors or assumptions |
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Bulk density |
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Classification |
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Audits or reviews |
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Discussion of relative accuracy/ confidence |
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1.5 JORC TABLE 1 – SECTION 4 ESTIMATION AND REPORTING OF ORE RESERVES
Ore Reserves are not reported so this is not applicable to this report.