Alderan Resources Limited (ASX: AL8) has received positive in-fill soil sample assay results for the Detroit project area in the Drum Mountains region of western Utah, USA and first pass gold recovery results for samples collected from drill holes completed at the Mizpah and Drum prospects at Detroit.
The in-fill soil sampling was carried out to better delineate anomalies identified in 2021 along a two km strike length of prospective host stratigraphy and along interpreted structural zones.
The gold recovery work was aimed at giving an initial indication of potential heap leach recoveries from oxide, mixed oxide-sulphide and sulphide mineralisation.
“Alderan’s in-fill soil sampling has better defined and enhanced the Mizpah, Basin Main and Midway anomalies with gold grades up to 0.32g/t Au,” Managing Director Scott Caithness said.
“It has also identified the more subtle Section 32 anomaly which appears to align along an interpreted NE-SW structure which trends towards the Mizpah deposit. The anomalies all occur over multiple 100m spaced soil lines.
“First pass gold recovery test work on oxide mineralisation in reverse circulation drill hole chips from Mizpah and Drum show encouraging recoveries of 66% and 95% respectively. Gold mineralisation is from surface at Mizpah and the depth of oxidation down Alderan’s drill holes ranges from 3-38m from surface.
“At Drum the mineralised oxide host horizons have been intersected below un-oxidised units at depths of greater than 70m below surface. Both Drum and Mizpah mineralisation remain open to the southwest.
“Alderan’s next step will be to compile and review all the drilling, soil geochemistry and first pass gold recovery data from its exploration at Detroit ahead of determining its 2023 exploration programme.”
The Mizpah soil anomaly is significantly larger than previously identified and contains gold grades up to 0.26g/t Au. It now occurs over five lines covering a north-south strike length of 300m and has an east-west width of up to 400m. The strike length of the anomaly is consistent with the distance covered by gold mineralised intersections in Alderan drill holes completed in September 2022 however the width of the anomaly is 400m, significantly wider than the 250m covered by Alderan’s drilling.
This supports Alderan’s conclusion from its drilling that the Mizpah gold mineralisation is open down dip to the west and southwest.
The Basin Main gold in soil anomaly is larger and higher order than Mizpah with grades up to 0.32g/t Au. It lies 800m north of Mizpah in the same rock unit however it is on the contact of the Basin porphyry intrusive stock which contains low-grade gold and copper mineralisation intersected in Alderan and historical drilling.
The soil anomaly occurs over four lines covering a north-south distance of 500m and along lines the anomaly reaches an east-west width of 480m. Drilling at Detroit in the 1960’s intersected chalcocite copper mineralisation immediately to the west of the soil anomaly on the margin of the Basin Porphyry however historical reports contain no gold assays.
The Midway anomaly, 800m to the south of Mizpah, contains grades up to 0.19g/t Au. It occurs over two lines (200m north-south) and reaches an east-west width of 200m along lines. It appears to have a northeast-southwest orientation which is consistent with the prevailing structural trend throughout the Detroit district, including at the Drum gold mine 800m to the south.
The Section 32 anomaly located in Detroit’s northeast tenement is lower order with a maximum assay of 0.056g/t Au. It occurs over 500m (five lines), has a maximum east-west width of 160m and has a prominent northeast- southwest trend. Mizpah lies 1.5km to the southwest along this structural trend.
Conclusions and Next Steps
Alderan’s key conclusion from the soil sampling and first pass gold recovery results include:
• The Basin Main, Midway and Section 32 gold in soil anomalies represent new targets within the Detroit District which have received no previous gold exploration
• Basin Main is a higher order anomaly than Mizpah and covers a larger area while the Midway and Section 32 gold anomalies are potentially structurally controlled
• First pass gold recovery testwork suggests that cyanide heap leaching may be a suitable gold extraction technique for oxidised and mixed oxide-sulphide mineralisation
Alderan’s next step will be reviewing all drill hole, soil and gold recovery data ahead of determining its 2023 Detroit exploration programme.
For further information please visit: https://alderanresources.com.au/
