Detroit

Our flagship project Detroit has potential for intrusive-related gold deposits.

It lies within the Detroit Mining District, 290km southwest of Salt Lake City, and contains numerous historical copper, gold and manganese mines. Past mining dates back to the 1870s and historical reports indicate production of ~125,000oz gold and 25,000t manganese. Historical exploration in the 1960s also delineated the thin, low-grade Basin Porphyry chalcocite copper deposit on the eastern margin of the Basin Porphyry complex.

Detroit lies within the east-west trending Tintic igneous belt and Alderan believes it has geological similarities to the Bingham copper-gold-molybdenum mining district further north in Utah, and the Battle Mountain and Carlin gold and copper mining districts in Nevada, both of which host world-ranked gold and copper mines.  Potential copper and gold deposit styles at Detroit include porphyry, distal disseminated, skarn, carbonate replacement and structurally controlled.

Detroit is within the Tintic Eocence igneous belt and has potential for mineral deposit styles which occur in the Bingham Belt and the Carlin and Battle Mountain trends in Utah and neighbouring Nevada. (Modified from: Johnson, C.L et al; Toward a Global Carlin-Type Exploration Model: The Relationship between Eocene Magmatism and Diverse Gold Rich deposits in the Great Basin, USA; Nov 2020)

Alderan controls 26km2 of tenements at Detroit through a series of option agreements with companies such as Tamra Mining LLC and Freeport McMoRan plus several local claim owners. The district has been explored for copper and gold by major mining companies such as Anaconda Copper, Kennecott, Newmont, BHP and Freeport but no one company was able to build a contiguous land position to enable district-wide modern exploration. The US Geological Survey (USGS) also explored the area, sampling extensive gold mineralised jasperoids.

Following completion of district scale exploration at Detroit in 2021 consisting of soil and rock sampling, magnetic and induced polarisation geophysical surveys plus diamond drilling, Alderan reduced its tenement holding and is now focused on advancing the Drum and Mizpah gold prospects.

Alderan owned and optioned tenement area at Detroit

Drum

Latest Announcements:

The Drum oxide gold deposit was mined from the adjacent East and West open pits between 1984-89 and produced 125,000 oz gold at a grade of approximately 1.2g/t Au.  Prior to Alderan commencing work, it had received no exploration since mining ceased.

Alderan’s exploration since acquiring Drum at the end of September 2021 includes reviewing and modelling historical drill hole data, geological mapping, rock sampling and diamond drilling.  This has verified the potential for both remnant gold mineralisation left behind when mining ceased plus new mineralisation as the mineralised horizons are open down dip and along strike.  Key findings from the review and modelling of historical drilling data include:

  • Exploration potential exists for 42-60Koz Au grading 1.1-1.4g/t left behind when mining ceased. This estimate is constrained to the historical drillholes while the deposit is open down dip and along strike to the south.

It should be noted that this exploration potential quantity and grade is conceptual in nature, that there has been insufficient exploration to estimate a Mineral Resource and that it is uncertain if further exploration will result in the estimation of a Mineral Resource.

  • There are high grade assays up to 38.8g/t Au over 1.5m sample intervals and high grade intersections including:
    • 7m @ 6.4g/t Au including 4.6m @ 18.1g/t Au (YC-58A)
    • 9m @ 5.0g/t Au including 9.1m @ 10.8g/t Au (YC-113A)
    • 2m @ 4.5g/t Au including 6.1m @ 10.3g/t Au (YC-174)
    • 1m @ 4.3g/t Au including 18.3m @ 7.7g/t Au (YC-169)
    • 1m @ 3.2g/t Au including 15.2m @ 6.4g/t Au (YC-242
  • Average drill hole depth was shallow at less than 50m.
  • No exploration was done for primary gold mineralisation below the oxide ore.

Alderan rock sampling of pit walls confirmed the presence of remnant oxide gold mineralisation with high grades up to 10.7g/t Au.  A total of 75 samples were collected with 34 assaying +0.5g/t Au and 20 assaying +1g/t Au.

Alderan in-pit rock samples which grade up to 10.65g/t Au.

Alderan completed an eight hole (868.6m) diamond drilling programme at Drum in Q1 2022 with the objective of confirming the presence of remnant gold mineralisation modelled from historical drill hole data in and around the open pits. All verification holes successfully intersected gold mineralisation grading +1g/t Au:

  • 9DD22-001: 3m @ 2.9g/t Au within 16.2m @ 1.0g/t Au below north end of East Pit;
  • 9DD22-003: 5m @ 2.5g/t Au within 17.8m @ 1.7g/t Au below south end of East Pit;
  • 9DD22-004: 1m @ 2.3g/t Au from surface at mined north end of West Pit;
  • 9DD22-005: 2m @ 2.0g/t Au from surface at mined north end of West Pit;
  • 9DD22-006: 1m @ 1.1g/t Au from surface at mined south end of West Pit;
  • 9DD22-007: 9m @ 0.42g/t Au (waste dump) and 5.9m @ 1.2g/t Au 150m down dip of West Pit (hole did not reach target depth).

Alderan and historical drill hole locations and mineralised intersections at Drum

Key conclusions following interpretation of the drill results and completion of the first phase of Drum exploration include:

  • Structure has played an important role in controlling mineralisation with the deposit sitting within a 400m wide and 600m long NE-SW open structural corridor.
  • The mineralisation is oxidised and likely suitable for heap leaching (the historical Drum mine was a heap leach operation).
  • The overall grade of Alderan’s gold intersections is consistent with the reported historical mined grade of 1.1-1.2g/t Au.
  • Mineralised intersections below the East Pit are 15-20m thick and suggest that the host Tatow unit has a shallow ~25o SW dip however the mineralisation can extend into geological units which were not the focus of historical mining.
  • Alderan’s West Pit mineralised intersections are likely thinner than true thickness as the holes were all collared in mined areas in the pit.
  • Hole 9DD22-007 indicates there is potential for significant gold mineralisation in waste dumps that surround the open pits.
  • The deep intersection in hole 9DD22-007 confirms gold mineralisation 150m down dip of the West Pit boundary but is incomplete as it did not fully traverse the host Chisholm Formation.
  • The potential for high grade, structurally controlled primary gold mineralisation associated with bedding parallel thrusting and high angle faults has never been tested.

Drum geology with pit outlines, Alderan drillholes and major structures.

Drum cross section highlighting down dip potential of historically mined mineralised formations.

Mizpah

Latest Announcements:

At Mizpah, 2km north of Drum, Alderan has reviewed and modelled the historical drill data and completed one diamond hole aimed at testing for down dip extensions 350m west of the north-western margin of the known deposit.  This hole intersected 69m @ 0.18g/t Au from 87.5m downhole.

The key conclusions following completion of this phase of exploration are:

  • The historically outlined Mizpah oxide gold deposit has exploration potential for 3.0-4.0Mt at a grade of 0.4-0.8g/t gold (40,000-100,000 ounces). This estimate is constrained to the historical drillholes while the deposit is open down dip and along strike to the north and south.

It should be noted that this exploration potential quantity and grade is conceptual in nature, that there has been insufficient exploration to estimate a Mineral Resource and that it is uncertain if further exploration will result in the estimation of a Mineral Resource.

  • There are high grade oxide gold intersections including:
    • 6m @ 2.3g/t Au (MZ-104)
    • 7m @ 1.9g/t Au (MZ-49)
    • 2m @ 1.7g/t Au (MZ-93)
    • 8m @ 1.4g/t Au (MZ-87-048)
    • 8m @ 1.14g/t Au (MZ-87-052) – last assay 9.1g/t Au
  • The mineralised system could be signficantly larger than modelling of historical drill holes indicates. Alderan’s holes DD20M-006 (83m @ 0.41g/t Au) and 3DD22-001, located 150m and 350m to the west respectively, are not included in the model.
  • The deposit remains open at depth with 40 historical holes ending in +0.5g/t Au and 20 ending in +1g/t Au. The highest grade last assay in a hole is 9.1g/t Au.
  • Average historical hole depth was only 28m and there are indications that a second mineralised horizon exists at depth.
  • Gold mineralisation not only occurs in the Chisholm Formation and Tatow unit, the mined horizons at Drum, but also in the Howell Limestone which separates the Chisholm and Tatow.
  • Mizpah mineralisation occurs from surface, dips gently and is un-mined hence if a mineable deposit was discovered, it would likely have a low stripping ratio.

Mizpah plan showing location of the deposit modelled from historical drilling and the location of Alderan drill holes including DD20M-006 and 3DD122-001 which indicate that the mineralising system is much larger.

Alderan’s next steps at Drum and Mizpah are to delineate the extent of the oxide gold mineralisation and explore for high grade primary mineralisation below the oxide.  ‘Sighter’ metallurgical testwork will also be carried out.

Detroit Background

Alderan district scale exploration at Detroit prior to entering the option over Drum gold mine included historical data compilation, tenement consolidation, geological mapping, stream, rock and soil sampling, ground magnetic and induced polarisation geophysical surveys plus diamond drilling to prioritise prospects.

Detroit geology and Alderan rock samples containing +2g/t Au. The Drum gold mine area was optioned to Alderan after this work was completed.

Detroit geology and Alderan rock samples containing +1% Cu

Prior to tenement consolidation, the Company drilled seven diamond holes focussed in and around the Mizpah gold-silver prospect on Tamra joint venture ground. All holes intersected gold mineralisation with the best grades in hole DDM20-006 which intersected 7m grading 1.98g/t gold within a broad 83m intercept grading 0.41g/t gold. Historical exploration in the mid-1980s for a near-surface oxide gold deposit at Mizpah included 197 holes drilled to an average depth of less than 30m. Forty of the holes ended in highly anomalous mineralisation grading more than 0.5g/t gold and of these, twenty holes ended in +1g/t gold.

Alderan’s exploration has highlighted Detroit’s potential to host skarn, intrusive and structure related copper and gold mineralisation within and on the margins of the Basin Porphyry complex. Bulk leach extraction gold (BLEG) stream sediment samples draining the Basin Porphyry, Copperhead and Mizpah prospects are highly anomalous in copper and gold and supported by rock samples.  Of 197 rock samples collected by Alderan, 17 graded >0.5% copper and 28 graded >1 g/t gold with maximum assays 3.2% copper and 9.1 g/t gold.  Results support historical rock sample analyses including jasperoid samples collected by the US Geological Survey which graded up to 100g/t Au.

Bulk leach extraction gold (BLEG) in stream catchments and +2g/t gold in Alderan rock samples at Detroit. The Drum gold mine area in the southeast was optioned to Alderan after this work was completed.

Copper in stream catchments and +1% copper in rock samples at Detroit

Following the stream and rock sampling, Alderan completed ground magnetic and induced polarisation (IP) geophysical surveys over the highest priority area. The ground magnetics identified anomalies likely to be caused by intrusives, associated skarns and structures and the IP highlighted chargeable zones which were interpreted to be caused by sulphide mineralisation potentially containing copper and gold.

The Basin Complex has a classic porphyry geophysical signature over 500m east-west by 300m north-south.  The central Basin Main magnetic anomaly is surrounded by a low magnetic arc followed by an outer rim of variable magnetics.   The IP chargeability anomaly covers and wraps around the magnetic anomaly and also highlights targets such as Mizpah, Copperhead, Southern and Northern Extension peripheral to the intrusive complex.

Basin Complex 3D inversion model chargeability anomaly (20-30 millisecond shell; yellow) overlying the Basin Main magnetic anomaly (>0.03 SI units cutoff; red) showing the location of all Alderan and historical holes. Drilling is planned on sites Y and P to test the Chargeability Stem and Skarn anomalies respectively.

During the last quarter of 2021, Alderan completed a 1,707m drilling programme consisting of six diamond holes to test coincident geophysical and geochemical anomalies for porphyry copper and distal disseminated gold mineralisation.  The objectives of the drilling were to intersect economic grades of copper and/or gold mineralisation, identify the cause of the anomalies and prioritise prospects for further exploration.

Exploration also commenced on the historical Drum oxide gold mine, located 2km south of Mizpah, following the execution of an option agreement with North Exploration LLC.   Drum produced ~125,000 oz of gold between 1984-89 from an oxide heap leach operation and had received no exploration since ceasing production.

Assays for samples from the 2021 drilling programme were locally anomalous in copper and gold however the grades and intersection thicknesses were not sufficiently encouraging to warrant further drilling on the targets tested.  Alderan is now focused on the Drum and Mizpah gold prospects which have potential for both near surface high grade oxide and primary structure controlled gold mineralisation.

3D image of Detroit inversion modelled magnetics (red isosurface cutoff >0.03 SI units) and IP chargeability (yellow isosurface cutoff >40 msec) geophysics showing the Basin complex anomalies; View looking northwest.

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