Initial exploration indicates that the high grade OREX copper prospect could be bigger than Eagle Mountain’s (ASX:EM2) flagship Oracle Ridge mine, just 3km away.

Following an initial geological review in 2020, Eagle Mountain Mining staked a significant package of prospective land called OREX near the high grade 184,000t (and growing) Oracle Ridge copper mine in Arizona.

Field mapping at the OREX prospect subsequently identified widespread outcropping mineralisation along the lower Leatherwood intrusive contact, ~3km from the Oracle Ridge mine portals.

This contact shows very similar geology to that encountered at the Oracle Ridge mine and covers an even greater area, traced by Eagle Mountain for over 4km:

Numerous high-grade rock chip samples were picked up along the contact, including 10.6% copper and 29.5 g/t silver; and 8.17% copper, 71.3 g/t silver and 0.48 g/t gold.

The results of this latest field work indicates that OREX is an outstanding target.

The physical characteristics of the mineralisation and the assay results are broadly consistent with those encountered at the Oracle Ridge mine, Eagle Mountain says.

The lower contact at OREX can be traced at surface for over 4km “and displays discontinuous skarn alteration and mineralisation over its entire length”, the company says.

Based on Eagle Mountain’s recent mapping and review of historical drilling information, the company believes the prospective contact exists at depth below the Leatherwood for ~3km in an east-west direction.

“These results illustrate the prospectivity of the OREX prospect which covers an area greater than at the Oracle Ridge mine,” Eagle Mountain Mining chief exec Tim Mason says.

“This is truly exciting.

“This latest field program on OREX concluded that the lower contact of the Leatherwood granitic intrusive has abundant outcropping copper skarn.

“Our interpretation is that the limestone units which host the mineralised skarn were intruded by the Leatherwood granite, therefore the bottom of the Leatherwood at OREX is highly prospective for further mineralisation.

“We have commenced a detailed drone aeromagnetic geophysical survey over OREX to assist us in defining priority drill targets.”

Next Steps

This drone aeromagnetic geophysical survey is currently being completed over the OREX prospect.

The survey will highlight areas with high magnetite content, a mineral often associated with mineralisation at Oracle Ridge.

After the survey, further geophysical processing of the data will be completed to establish the depth of the anomalies, Eagle Mountain says.

Drill holes will then be planned to test these anomalies in the coming months, and drilling will commence once necessary permits are received.


This article was developed in collaboration with Eagle Mountain, a Stockhead advertiser at the time of publishing.


This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.