TORONTO, Sept. 27, 2022 (GLOBE NEWSWIRE) -- Xanadu Mines Ltd (ASX: XAM, TSX: XAM) (Xanadu or the Company) is pleased to announce initial trenching results from the 100% owned Red Mountain project located within the Dornogovi Province of southern Mongolia, approximately 420km southeast of Ulaanbaatar and 70km west of the provincial centre of Sainshand.
Highlights
Assays returned for 1,170m of the 6,500m trenching program at Red Mountain.
Initial focus on Target 33 (T33) returned a broad zone of shallow gold mineralisation.
Significant intercepts include OUTR109 with 66m @ 0.37g/t Au from 26m,
including 18m @ 0.81g/t Au from 50m,
including 10m @ 1.23g/t Au from 58m.
OUTR109 results, combined with historic trenching results, define a 350m x 80m zone of highly anomalous gold, including a higher-grade core greater than 1g/t Au.
Anomalous gold zone remains open to the west and a future drill program will test 50m below this zone in multiple sections.
Trenching continues to test additional targets for surface gold and copper mineralisation across the 57m2 tenement.
Xanadu’s Executive Chairman & Managing Director, Colin Moorhead said: “We are encouraged by this solid start to the Red Mountain trenching program. Initial results from T33 outline a zone of strongly anomalous gold (greater than 0.2g/t Au) at surface that extends for 350m along strike and 80m wide, and within this zone is a higher-grade core (greater than 1g/t Au). We look forward to the remaining trenching assays, which will define our future drill program for Red Mountain.
T33 Trenching
Assays have been returned at T33 for approximately 1,170m of trenching over seven trenches, targeting an area of high-grade gold identified in previous trenching and drilling. Assay results returned broad zones of anomalous gold (Table 1 and Figure 1), associated with felsic intrusive and strong alteration.
When combined with previous work at T33 1,2, these new results expand upon the previous broad, highly anomalous gold zone at surface to a current interpretation of approximately 350m long and 80m wide, including a higher-grade core greater than 1g/t Au. This anomalous gold zone remains open to the west and will be investigated through a drill program of stab holes designed to test approximately 50m below this zone in multiple sections.
Xanadu is undertaking a disciplined and systematic exploration program, which includes:
Detailed geological work, 3D geophysical and geochemical modelling;
Trenching to test strike extent and develop drill targets; and
Drill program focussed on shallow gold, silver and copper targets.
This announcement reports trenching results from the initial 1,170 horizontal metres of a planned 6,500 metre program. The program is designed to test strike extent and develop targets for follow-up diamond drilling program.
Surface trenching has proven to be a rapid and economic target definition approach prior to diamond drilling, and this program will include extensive trenching over several new, gold, silver and copper targets.
About Red Mountain
Xanadu’s Red Mountain porphyry copper-gold-silver project is located within the Dornogovi Province of southern Mongolia, approximately 420km southeast of Ulaanbaatar (Figure 2), and 70km west from the provincial centre of Sainshand. The project has a granted 30-year mining licence and comprises an underexplored porphyry district (covering approximately 57km²).
FIGURE 2: Location of Red Mountain in the South Gobi region of Mongolia
Red Mountain mineralisation is associated with late-stage monzonite and quartz diorite porphyry dykes and stocks emplaced on the flanks of the Red Mountain Intrusive Complex (Figure 3). This consists of multiple co-genetic porphyry gold and copper centres, mineralised tourmaline breccia pipes, gold and copper base metal magnetite skarns and epithermal gold veins.
Previous exploration at Red Mountain has defined several broad zones of strongly mineralised quartz stockwork veining associated with high-grade gold and increasing alteration strength, with the mineralisation style suggesting strong likelihood for depth extensions.
FIGURE 3: Red Mountain Mining Licence, showing ground Landsat data, gold geochemistry and priority targets
Shallow gold-rich and silver-rich copper mineralisation has been identified in numerous zones, located within a 4.5km long and 300m wide prospective mineralisation zone. This mineralisation is primarily located in Bavuu, Stairy, Diorite, Target 33, Nowie and Stockwork (Figure 3). Broad spaced drilling has confirmed gold mineralisation is hosted by hematite-quartz veins with coarse visible gold, occurring as multiple stacked arrays. Veins are typically narrow, but very high-grade with gold assays ranging from 1 g/t to >30 g/t gold over widths of 0.5m to 1.5m. Mineralised veins are characterised by banded and crustiform quartz and abundant sulphides. All these features are commonly found in the lower boiling zone of epithermal system, where bonanza grades are expected.
In addition to shallow, high-grade mineralisation, Red Mountain has potential for large-scale porphyry at depth. Highly anomalous geochemistry corresponds to broad zones of porphyry mineralisation from trenching, zoned porphyry alteration, overlapping with large-scale magnetic and gravity anomalies, representing a compelling string of very large porphyry targets over 6km strike (Figure 3). Initial deeper drilling in 2017 encountered 200-300m wide zones of porphyry style mineralisation at Target 10.
About Xanadu Mines
Xanadu is an ASX and TSX listed Exploration company operating in Mongolia. We give investors exposure to globally significant, large-scale copper-gold discoveries and low-cost inventory growth. Xanadu maintains a portfolio of exploration projects and remains one of the few junior explorers on the ASX or TSX who control a globally significant copper-gold deposit in our flagship project. For information on Xanadu visit: www.xanadumines.com
Colin Moorhead Executive Chairman & Managing Director Xanadu Mines Ltd info@xanadumines.com +61 2 8280 7497 This Announcement was authorised for release by Xanadu’s Executive Chairman & Managing Director.
Appendix 1: Trenching Results
Table 1: Trench Locations at T33
Trench ID
Prospect
East
North
RL
Azimuth (°)
Inc (°)
Length (m)
OUTR108
Target 33
373812
4938096
1068
175
-5
176.0
OUTR109
Target 33
373858
4938085
1063
173
-4
173.0
OUTR110
Target 33
374095
4938100
1050
178
-2
178.0
OUTR111
Target 33
374147
4938108
1067
179
-6
179.4
OUTR112
Target 33
374201
4938116
1063
180
-6
150.0
OUTR113
Target 33
374247
4938138
1060
179
-4
144.0
OUTR114
Target 33
374296
4938165
1054
179
-2
170.4
Table 2: Significant 2022 Trenching Intercepts from T33
Trench ID
From (m)
To (m)
Interval (m)
Au (g/t)
Cu (%)
OUTR108
10
36
26
0.20
0.06
including
16
30
14
0.32
0.05
and
46
62
16
0.20
0.21
and
72
116
44
0.16
0.07
OUTR109
26
92
66
0.37
0.04
including
50
82
32
0.60
0.04
including
50
68
18
0.81
0.05
including
58
68
10
1.23
0.09
and
106
110
4
0.97
0.04
OUTR110
10
18
8
0.13
0.06
and
80
86
6
0.12
0.03
and
100
116
16
0.10
0.08
and
130
140
10
0.16
0.01
and
156
160
4
0.15
0.04
OUTR111
54
72
18
0.17
0.07
OUTR113
110
126
16
0.11
0.02
OUTR114
10
16
6
0.12
0.06
Appendix 2: Statements and Disclaimers
Competent Person Statements
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 (JORC Code, 2012) 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.
Forward-Looking Statements
Certain statements contained in this Announcement, including information as to the future financial or operating performance of Xanadu and its projects may also include statements which are ‘forward‐looking statements’ that may include, amongst other things, statements regarding targets, estimates and assumptions in respect of mineral reserves and mineral resources and anticipated grades and recovery rates, production and prices, recovery costs and results, capital expenditures and are or may be based on assumptions and estimates related to future technical, economic, market, political, social and other conditions. These ‘forward-looking statements’ are necessarily based upon a number of estimates and assumptions that, while considered reasonable by Xanadu, are inherently subject to significant technical, business, economic, competitive, political and social uncertainties and contingencies and involve known and unknown risks and uncertainties that could cause actual events or results to differ materially from estimated or anticipated events or results reflected in such forward‐looking statements.
Xanadu disclaims any intent or obligation to update publicly or release any revisions to any forward‐looking statements, whether as a result of new information, future events, circumstances or results or otherwise after the date of this Announcement or to reflect the occurrence of unanticipated events, other than required by the Corporations Act 2001 (Cth) and the Listing Rules of the Australian Securities Exchange (ASX) and Toronto Stock Exchange (TSX). The words ‘believe’, ‘expect’, ‘anticipate’, ‘indicate’, ‘contemplate’, ‘target’, ‘plan’, ‘intends’, ‘continue’, ‘budget’, ‘estimate’, ‘may’, ‘will’, ‘schedule’ and similar expressions identify forward‐looking statements.
All ‘forward‐looking statements’ made in this Announcement are qualified by the foregoing cautionary statements. Investors are cautioned that ‘forward‐looking statements’ are not guarantee of future performance and accordingly investors are cautioned not to put undue reliance on ‘forward‐looking statements’ due to the inherent uncertainty therein.
For further information please visit the Xanadu Mines’ Website at www.xanadumines.com.
Appendix 3: Red Mountain Table 1 (JORC Code, 2012)
Set out below is Section 1 and Section 2 of Table 1 under the JORC Code, 2012 for the Red Mountain project. Data provided by Xanadu. This Table 1 updates the JORC Table 1 disclosure dated 24 August 2022.5
1.1 JORC TABLE 1 - SECTION 1 - SAMPLING TECHNIQUES AND DATA
Criteria
Commentary
Sampling techniques
The exploration results are based on diamond drill core samples, reverse circulation (RC) chip samples and channel samples from surface trenches.
Representative ½ core samples were split from PQ, HQ & NQ diameter diamond drill core on site using rock saws, on a routine two metre sample interval that also honours lithological/intrusive contacts.
The orientation of the cut line is controlled using the core orientation line ensuring uniformity of core splitting wherever the core has been successfully oriented.
Sample intervals are defined and subsequently checked by geologists, and sample tags are attached (stapled) to the plastic core trays for every sample interval.
RC chip samples are ¼ splits from 1m intervals using a 75%:25% riffle splitter to obtain a 3kg sample.
RC samples are uniform 2m samples formed from the combination of two ¼ split 1m samples.
Trench samples are collected as 2m composite from 30m above the trench toe.
Sampling generally honours lithological contacts.
Trench samples are continuous along the length of the trench
Drilling techniques
The exploration results are based upon diamond drilling of PQ, HQ and NQ diameters with both standard and triple tube core recovery configurations, RC drilling and surface trenching with channel sampling.
All drill core drilled by Xanadu has been oriented using the “Reflex Ace” tool.
Drill sample recovery
Diamond drill core recoveries were assessed using the standard industry (best) practice which involves removing the core from core trays; reassembling multiple core runs in a v-rail; measuring core lengths with a tape measure, assessing recovery against core block depth measurements and recording any measured core loss for each core run.
Diamond core recoveries average 97% through mineralisation.
Overall, core quality is good, with minimal core loss. Where there is localised faulting and or fracturing core recoveries decrease, however, this is a very small percentage of the mineralised intersections.
RC recoveries are measured using whole weight of each 1m intercept measured before splitting
Analysis of recovery results vs grade shows no significant trends that might indicate sampling bias introduced by variable recovery in fault/fracture zones.
Logging
All drill core is geologically logged by well-trained geologists using a modified “Anaconda-style” logging system methodology. The Anaconda method of logging and mapping is specifically designed for porphyry Cu-Au mineral systems.
Logging of lithology, alteration and mineralogy is intrinsically qualitative in nature. However, the logging is subsequently supported by 4 Acid ICP-MS (48 element) geochemistry and SWIR spectral mineralogy (facilitating semi-quantitative / calculated mineralogical, lithological and alteration classification) which is integrated with the logging to improve cross section interpretation and 3D geological model development.
Drill core is also systematically logged for both geotechnical features and geological structures. Where drill core has been successfully oriented, the orientation of structures and geotechnical features are also routinely measured.
Both wet and dry core photos are taken after core has been logged and marked-up but before drill core has been cut.
Sub -sampling techniques and sample preparation
All drill core samples are ½ core splits from either PQ, HQ or NQ diameter cores. A routine 2m sample interval is used, but this is varied locally to honour lithological/intrusive contacts. The minimum allowed sample length is 30cm.
Core is appropriately split (onsite) using diamond core saws with the cut line routinely located relative to the core orientation line (where present) to provide consistency of sample split selection.
The diamond saws are regularly flushed with water to minimize potential contamination.
A field duplicate ¼ core sample is collected every 30th sample to ensure the “representivity of the in-situ material collected”. The performance of these field duplicates is routinely analysed as part of Xanadu’s sample QC process.
Routine sample preparation and analyses of DDH samples were carried out by ALS Mongolia LLC (ALS Mongolia), who operates an independent sample preparation and analytical laboratory in Ulaanbaatar.
All samples were prepared to meet standard quality control procedures as follows: Crushed to 75% passing 2mm, split to 1kg, pulverised to 85% passing 200 mesh (75 microns) and split to 150g sample pulp.
ALS Mongolia Geochemistry labs quality management system is certified to ISO 9001:2008.
The sample support (sub-sample mass and comminution) is appropriate for the grainsize and Cu-Au distribution of the porphyry Cu-Au mineralization and associated host rocks.
Trench samples by previous explorers between 2001 to 2007 were prepared and assayed by SGS Mongolia.
Quality of assay data and laboratory tests
All XAM samples were routinely assayed by ALS Mongolia for gold.
Au is determined using a 25g fire assay fusion, cupelled to obtain a bead, and digested with Aqua Regia, followed by an atomic absorption spectroscopy (AAS) finish, with a lower detection limit (LDL) of 0.01 ppm.
All samples were also submitted to ALS Mongolia for the 48-element package ME-ICP61 using a four-acid digest (considered to be an effective total digest for the elements relevant to the MRE). Where copper is over-range (>1% Cu), it is analysed by a second analytical technique (Cu-OG62), which has a higher upper detection limit (UDL) of 5% copper.
Quality assurance has been managed by insertion of appropriate Standards (1:30 samples - suitable Ore Research Pty Ltd certified standards), Blanks (1:30 samples), Duplicates (1:30 samples - ¼ core duplicate) by Xanadu.
Assay results outside the optimal range for methods were re-analysed by appropriate methods.
Ore Research Pty Ltd certified copper and gold standards have been implemented as a part of QC procedures, as well as coarse and pulp blanks, and certified matrix matched copper-gold standards.
QC monitoring is an active and ongoing processes on batch-by-batch basis by which unacceptable results are re-assayed as soon as practicable.
Prior to 2014: Cu, Ag, Pb, Zn, As and Mo were routinely determined using a three-acid-digestion of a 0.3g sub-sample followed by an AAS finish (AAS21R) at SGS Mongolia. Samples were digested with nitric, hydrochloric and perchloric acids to dryness before leaching with hydrochloric acid to dissolve soluble salts and made to 15ml volume with distilled water. The LDL for copper using this technique was 2ppm. Where copper was over-range (>1% Cu), it was analysed by a second analytical technique (AAS22S), which has a higher upper detection limit (UDL) of 5% copper. Gold analysis method was essentially unchanged.
Trenching samples from 2001 to 2007 were analysed for 6 elements (Cu, Ag, Pb, Zn, As and Mo) by SGS Mongolia using a three-acid-digestion of a 0.3g sub-sample followed by an AAS finish (AAS21R). Samples were digested with nitric, hydrochloric and perchloric acids to dryness before leaching with hydrochloric acid to dissolve soluble salts and made to 15ml volume with distilled water. The LDL for copper using this technique was 2ppm. Where copper was over-range (>1% Cu), it was analysed by a second analytical technique (AAS22S), which has a higher upper detection limit (UDL) of 5% copper. Gold analysis method was essentially unchanged.
Verification of sampling and assaying
All assay data QA/QC is checked prior to loading into Xanadu’s Geobank data base.
The data is managed by Xanadu geologists.
The data base and geological interpretation is managed by Xanadu.
Check assays are submitted to an umpire lab (SGS Mongolia) for duplicate analysis.
No twinned drill holes exist.
There have been no adjustments to any of the assay data.
Location of data points
Diamond drill holes have been surveyed with a differential global positioning system (DGPS) to within 10cm accuracy.
The grid system used for the project is UTM WGS-84 Zone 49N
Historically, Eastman Kodak and Flexit electronic multi-shot downhole survey tools have been used at Red Mountain to collect down hole azimuth and inclination information for the majority of the diamond drill holes. Single shots were typically taken every 30m to 50m during the drilling process, and a multi-shot survey with readings every 3-5m are conducted at the completion of the drill hole. As these tools rely on the earth’s magnetic field to measure azimuth, there is some localised interference/inaccuracy introduced by the presence of magnetite in some parts of the Red Mountain mineral system. The extent of this interference cannot be quantified on a reading-by-reading basis.
More recently (since September 2017), a north-seeking gyro has been employed by the drilling crews on site (rented and operated by the drilling contractor), providing accurate downhole orientation measurements unaffected by magnetic effects. Xanadu have a permanent calibration station setup for the gyro tool, which is routinely calibrated every 2 weeks (calibration records are maintained and were sighted).
The project DTM is based on 1 m contours from satellite imagery with an accuracy of ±0.1 m.
Trenching locations for trenches between 2001 and 2007 were located using a handheld GPS.
Data spacing and distribution
Holes spacings range from <50m spacings within the core of mineralisation to +500m spacings for exploration drilling. Hole spacings can be determined using the sections and drill plans provided.
Holes range from vertical to an inclination of -60 degrees depending on the attitude of the target and the drilling method.
The data spacing and distribution is sufficient to establish anomalism and targeting for porphyry Cu-Au, tourmaline breccia and epithermal target types.
Holes have been drilled to a maximum of 1,300m vertical depth.
The data spacing and distribution is sufficient to establish geological and grade continuity.
Orientation of data in relation to geological structure
Drilling is conducted in a predominantly regular grid to allow unbiased interpretation and targeting.
Scissor drilling, as well as some vertical and oblique drilling, has been used in key mineralised zones to achieve unbiased sampling of interpreted structures and mineralised zones, and in particular to assist in constraining the geometry of the mineralised hydrothermal tourmaline-sulphide breccia domains.
Sample security
Samples are delivered from the drill rig to the core shed twice daily and are never left unattended at the rig.
Samples are dispatched from site in locked boxes transported on Xanadu company vehicles to ALS lab in Ulaanbaatar.
Sample shipment receipt is signed off at the Laboratory with additional email confirmation of receipt.
Samples are then stored at the lab and returned to a locked storage site.
Audits or reviews
Internal audits of sampling techniques and data management are undertaken on a regular basis, to ensure industry best practice is employed at all times.
External reviews and audits have been conducted by the following groups:
2012: AMC Consultants Pty Ltd. was engaged to conduct an Independent Technical Report which reviewed drilling and sampling procedures. It was concluded that sampling and data record was to an appropriate standard.
2013: Mining Associates Ltd. was engaged to conduct an Independent Technical Report to review drilling, sampling techniques and QA/QC. Methods were found to conform to international best practice.
1.2 JORC TABLE 1 - SECTION 2 - REPORTING OF EXPLORATION RESULTS (Criteria in this section apply to all succeeding sections).
Criteria
Commentary
Mineral tenement and land tenure status
The Project comprises 1 Mining Licence (MV-17129A).
Xanadu now owns 90% of Vantage LLC, the 100% owner of the Oyut Ulaan mining licence.
The Mongolian Minerals Law (2006) and Mongolian Land Law (2002) govern exploration, mining and land use rights for the project.
Exploration done by other parties
Previous exploration was conducted by Quincunx Ltd, Ivanhoe Mines Ltd and Turquoise Hill Resources Ltd including extensive drilling, surface geochemistry, geophysics, mapping.
Geology
The mineralisation is characterised as porphyry copper-gold type.
Porphyry copper-gold deposits are formed from magmatic hydrothermal fluids typically associated with felsic intrusive stocks that have deposited metals as sulphides both within the intrusive and the intruded host rocks. Quartz stockwork veining is typically associated with sulphides occurring both within the quartz veinlets and disseminated thought out the wall rock. Porphyry deposits are typically large tonnage deposits ranging from low to high grade and are generally mined by large scale open pit or underground bulk mining methods. The deposits at Red Mountain are atypical in that they are associated with intermediate intrusions of diorite to quartz diorite composition; however, the deposits are in terms of contained gold significant, and similar gold-rich porphyry deposits.
Drill hole Information
Diamond drill holes are the principal source of geological and grade data for the Project.
See figures in this ASX/TSX Announcement.
Data Aggregation methods
A nominal cut-off of 0.1% CuEq is used in copper dominant systems for identification of potentially significant intercepts for reporting purposes. Higher grade cut-offs are 0.3%, 0.6% and 1% CuEq.
A nominal cut-off of 0.1g/t AuEq is used in gold dominant systems like for identification of potentially significant intercepts for reporting purposes. Higher grade cut-offs are 0.3g/t, 0.6g/t and 1g/t AuEq.
Maximum contiguous dilution within each intercept is 9m for 0.1%, 0.3%, 0.6% and 1% CuEq.
Most of the reported intercepts are shown in sufficient detail, including maxima and subintervals, to allow the reader to make an assessment of the balance of high and low grades in the intercept.
Informing samples have been composited to two metre lengths honouring the geological domains and adjusted where necessary to ensure that no residual sample lengths have been excluded (best fit).
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 with a metallurgical recovery factor applied.
Copper equivalent (CuEq or eCu) grade values were calculated using the following formula:
CuEq = Cu + Au * 0.62097 * 0.8235,
Gold Equivalent (AuEq or eAu) grade values were calculated using the following formula:
AuEq = Au + Cu / 0.62097 * 0.8235
Where: Cu = copper grade (%); Au = gold grade (g/t); 0.62097 = conversion factor (gold to copper); 0.8235 = relative recovery of gold to copper (82.35%)
The copper equivalent formula was based on the following parameters (prices are in USD):
Copper price = 3.1 $/lb (or 6834 $/t)
Gold price = 1320 $/oz
Copper recovery = 85%
Gold recovery = 70%
Relative recovery of gold to copper = 70% / 85% = 82.35%.
Relationship between mineralisation on widths
and intercept lengths
Mineralised structures are variable in orientation, and therefore drill orientations have been adjusted from place to place in order to allow intersection angles as close as possible to true widths.
Exploration results have been reported as an interval with 'from' and 'to' stated in tables of significant economic intercepts. Tables clearly indicate that true widths will generally be narrower than those reported.
Diagrams
See figures in this ASX/TSX Announcement.
Balanced
Reporting
Exploration results have been reported at a range of cut-off grades, above a minimum suitable for open pit mining, and above a minimum suitable for underground mining.
Other substantive exploration data
Extensive work in this area has been done and is reported separately.
Further Work
The mineralisation is open at depth and along strike.
Current estimates are restricted to those expected to be reasonable for open pit mining. Limited drilling below this depth (-300m RL) shows widths and grades potentially suitable for underground extraction.
Exploration ongoing.
1.3 JORC TABLE 1 - SECTION 3 ESTIMATION AND REPORTING OF MINERAL RESOURCES
Mineral Resources are not reported so this is not applicable to this report.
1.4JORC TABLE 1 - SECTION 4 ESTIMATION AND REPORTING OF ORE RESERVES
Ore Reserves are not reported so this is not applicable to this report.
1 ASX Announcement 30 June 2016 - Further High-Grade Gold Intercepts at Oyut Ulaan 2 ASX Announcement 28 June 2017 – Oyut Ulaan Exploration Update: Strong Drill Results Across the District 3 ASX Announcement 30 June 2016 - Further High-Grade Gold Intercepts at Oyut Ulaan 4 ASX Announcement 28 June 2017 – Oyut Ulaan Exploration Update: Strong Drill Results Across the District 5 ASX/TSX Announcement 24 August 2022 – Exploration Ramps Up at Red Mountain
