The Butler East target is located 29 km west of Eagle’s Nest and forms the eastern limb of the Butler property (figure 1). Noront acquired a 75% interest in the property from MacDonald Mines in 2016. Past drilling in 2007 by MacDonald Mines targeting airborne mag-EM anomalies intersected low-grade Ni-sulfide mineralization associated with ferrogabbroic rocks (figure 2) within a sequence of mafic-ultramafic sills intruding sulfide-bearing mafic volcanic and metasedimentary rocks of the older (circa 2,820Ma) Butler Assemblage. To date no age dating of the mafic-ultramafic intrusions at Butler East has been performed so their relationship, if any, to the intrusions hosting Eagle’s Nest and the chromite deposits to the east remains unclear.
The area contains numerous airborne EM anomalies, many of which appear to be related to formational conductors, but some of which are associated with Ni mineralization in ferrogabbro. Mineralization intersected to date consists of low-grade disseminated Ni+/-Cu sulfides within Fe-rich ferrogabbroic sills, similar in respect to the Pechenga Ni camp in Russia. The appearance of fractionated ultramafic sills lower in the stratigraphy (figure 2) coupled with the abundance of sulfur-rich country rocks presents a compelling Ni exploration target at Butler East.