DevEx Resources Limited (ASX: DEV) announced that the encouraging soil geochemistry results together with analysis of recent drilling indicates the potential for a significant porphyry-copper-gold system, warranting further drilling at its Junee Copper-Gold Project in NSW.
The company reported that soil geochemistry results identified a large, coincident copper-gold soil anomaly up to 1km long at the Nangus Road Prospect within the Junee Project.
DEV noted that the results were enhanced by the recent identification of altered porphyry monzonite in diamond drill hole (JNDD003) completed last year, and are interpreted as characteristic of a mineralised porphyry copper-gold system.
DevEx said that an expanded geochemistry program has commenced, with follow-up air-core/RAB drilling planned to further evaluate the copper-gold anomaly in the coming months.
Encouraging soil geochemistry results
DEV said that age dating and chemistry from the area undertaken by the Geological Survey of New South Wales (GSNSW) identified monzonitic intrusions, such as the copper-gold bearing Cooba Monzonite, which are high-potassium in nature and the same age as the copper-gold mineralised intrusions at the major Cadia-Ridgeway and Northparkes mining operations to the north.
1 km long anomaly
DevEx reported that the reconnaissance soil sampling on the northern margin of the Nangus Road magnetic anomaly identified a broad coincident copper-gold in soil anomaly up to 1 kilometre long, which remains open to the south and west.
The company noted that the copper-gold soil anomaly is also supported by other pathfinder elements consistent with major porphyry copper-gold systems, including molybdenum, bismuth, tellurium.
Altered porphyry monzonite in JNDD003
The company had recently completed diamond drill hole JNDD003 last year, which had confirmed that an altered monzonite is the likely source of the Nangus Road magnetic anomaly.
The Nangus Road magnetic anomaly extends for 2km in a northerly direction, is approximately 2km wide, and lies beneath variable transported cover. It displays similar size and magnetic amplitude to the Ordovician aged Cooba Cu-Au bearing Monzonite to the north of the Project.
DEV said that hole JNDD003 passed through approximately 100m of young, transported cover before intersecting a hornblende, magnetite, and biotite-bearing monzonite intrusion with intense propylitic alteration.
DevEx reported that the geochemistry indicates that the rock is a porphyry-fertile, high-potassium intrusion. Mineralogical examinations of the most intense alteration zones indicate an assemblage of actinolite-albite-epidote in association with the very fine copper minerals chalcopyrite and bornite.
Potential for large-scale porphyry copper-gold system
DevEx said that the surface geochemical sampling results together with analysis of recent drilling supports potential for a significant porphyry-copper-gold system, warranting further drilling.
DEV has a large portfolio of tenements within the proven porphyry copper-gold region of NSW, where it continues to test several highly prospective targets.
Next steps
DEV said that the soil programme is now being expanded further to the south and west. The Company noted that the thickness of overburden is likely to increase to the south west and in so doing, compromise the effectiveness of the soil samples in seeing beneath the cover.
DevEx announced that it plans to further evaluate this prospective intrusion in more detail using a combination of geophysics and air-core or RAB drilling to bedrock in the coming months.
* Image courtesy DevEx Resources Limited