Home > Mining Companies > FNI > Articles > Dundonald
FNI

Dundonald

Oct 17, 2014
The Dundonald Property was acquired by FNI from Falconbridge Limited based primarily on its potential to host economic Kambalda-style Ni (+/- Cu, Co, PGE) sulphide deposits associated with ultramafic volcanics in the Dundonald South and Dundeal zones. FNI also recognized the potential for lower grade but larger tonnage nickel deposits in the Dundonald South area, for Cu-Zn base metal deposits in the Terminus/Dundeal area and for bulk tonnage PGE deposits in the Dundonald Sill.




 
The Dundonald Property is situated approximately 60 km northeast of Timmins, Ontario and totals 56 mining claim units covering 946 ha in Dundonald and Clergue townships. The property is owned 100% by FNI.

It is located, in the central-western portion of the Kidd-Munro assemblage of the Abitibi Subprovince of the Archean Superior Province. The geology of the property consists of a late differentiated tholeiitic mafic-ultramafic intrusion, the Dundonald Sill, which intrudes a sequence of komatiitic ultramafic-mafic volcanic flows separated by calc-alkaline intermediate-felsic volcanic flows. The property contains a 9.5 km strike length of highly prospective komatiitic volcanics for hosting Kambalda style nickel sulphide deposits. Two major areas of Kambalda style nickel mineralization occur within the komatiitic volcanics: Dundonald South and Dundeal.
 
The Dundonald property covers approximately 946 hectares in Clergue and Dundonald Townships in the Porcupine Mining Division and is well situated within two kilometers of a maintained paved roadway (formerly Highway 67), railway lines and power lines. Logging and drill roads provide general access throughout the Property





FNI is the recorded holder of a 100% interest in 15 unpatented claims, 38 mining leases, and 3 patented claims totalling ~946 ha in Clergue and Dundonald Townships in the Porcupine Mining Division of Ontario comprising the Dundonald Property (Figure 2). There is a 1.5% NSR reserved in favour of a third party on claim SEC 4177.

 
PREVIOUS WORK
 
1960 - 7 DDH completed for a total of 808 metres; Ground Geophysical and Geological surveys.
1962 - 4 DDH completed for a total of 364 metres; EM and Magnetic surveys.
1964 - 12 DDH completed for a total of 947 metres on Dundonald South.
1965 - 31 DDH completed for a total of 4,553 metres; detailed Magnetometer and EM surveys on Dundonald South.
1969 - 2,236 metres of DDH completed on Dundonald South
1972 - 3 DDH completed for a total of 491 metres
1973 - 4 DDH completed for a total of 518 metres on Dundonald South
1974 - 36 DDH completed for a total of 5,956 metres on upper 150 metres at Dundonald South
1989 - 14 DDH completed for a total of 6,723 metres; 8 DDH Dundonald South, 6 DDH Dundeal (discovery of nickel zone); surface Mag and EM surveys, Surface stripping of western portion of Dundonald South.
1990 - 22 DDH completed for a total of 10,444 metres on Dundeal; Terminus Cu-Zn zone discovered.
1991 - 18 DDH completed for a total of 6,970 metres on Dundeal and Terminus Zones.  Airborne EM, MAG and VLF surveys, 10 km of CHIM survey.  Discovery of PGE mineralization in Dundonald Sill (Casey’s Showing)
1993 - Borehole and surface TDEM, Mise a la Masse survey, 3 DDH completed for a total of 505 metres.
2001 - 13 DDH completed for a total of 2043 metres.  Surface stripping of 4 areas.


GEOLOGY
 
The Dundonald property is located in the southwestern part of the Abitibi Subprovince of the Archean Superior Province. The Abitibi Subprovince, or "greenstone belt" is the world's largest and best preserved example of an Archean upracrustal sequence. The Abitibi Subprovince is an assemblage of volcanic, sedimentary, and intrusive rocks deformed into a roughly east-trending, 200 km wide belt exposed from the Kapuskasing structure in Ontario to the Grenville orogeny in Quebec, a distance of approximately 400 km.
 
The geology on the Dundonald property is fairly complex consisting of a late differentiated tholeiitic intrusion, the Dundonald Sill, which intrudes a sequence of komatiitic volcanic rocks separated by calc-alkaline volcanic rocks. There appears to be at least four separate komatiitic sequences within the boundaries of FNI’s Dundonald property. 





Rocks present on the Dundonald Property include: massive intermediate feldspar crystal ash to lapilli tuff interlayered with massive to pillowed mafic volcanics; komatiite basalts to dunites, that host the nickel and base metal mineralization; interflow graphitic argillites are common within the komatiitic rocks; massive mafic volcanics; and intrusive theoleiitic peridotite to gabbro.

 
MINERALIZATION
 
Three main types of mineralization have been explored to varying degrees on the Dundonald Property. Foremost, the Kambalda Model of nickel sulphide mineralization hosted by the lowermost section of the komatiite volcanics at the Dundeal Zone (Ni) and at the Dundonald South Area (Ni). Volcanogenic massive sulphide mineralization occurs in the Terminus Zone (base metals), towards the top of the komatiites, and is hosted by a basaltic komatiite sequence. More recently, platinum and palladium mineralization has been discovered within a pyroxenite sub-unit of the Dundonald Sill.


Inferred Mineral Resource Results
 
G.A. Haron of MPH Consulting Ltd. was hired by the company to complete an NI 43-101 compliant resource estimate on the Dundonald South Deposit in January 2009.  A copy of the complete report was filled on SEDAR on January 30, 2009.
 
The resources estimated in the Dundonald South area are classified as Inferred Mineral Resources as defined by the CIM Standards on Mineral Resources and Reserves. Overall the mineralized zones that meet the grade (> 1.5% Ni) and thickness (2.0 m) parameters are small and isolated. This observation suggests that both geological and grade continuity are not strong features of the resource estimate and only warrant an inferred resource categorization.
 
The software used to generate the resource provides more of an “order of magnitude” result, which is appropriate for resource estimation purposes at this level of exploration
 
The contributions of the individual mineralized zones (A through H) to the total known resource is summarized in Table 13. The estimated inferred mineral resource for the Dundonald South nickel zones is 116,000 tonnes grading 3.16% Ni, with the A, F, and G zones contributing 67 % of the resource tonnage.


The quantity and grade reported in this inferred resource estimation are conceptual in nature and there has been insufficient exploration to define an indicated mineral resource on the property and it is uncertain if further exploration will result in discovery of an indicated or measured mineral resource on the property.

 
Dundonald South
 
The Dundonald South Nickel Area is readily separated into north and south sectors (Summary: First Nickel Drill Results to date on the Dundonald South Nickel Area; FND designates Dundonald South, North Sector; FNS designates Dundonald South, South Sector).
 
The north sector of the Dundonald South Area extends over a geophysically (Falconbridge MaxMin I, 1989) indicated strike length of 650-700 m. There appears to be at least four main mineralized horizons (A to D) associated with specific komatiite units within the overall Sector.





The more southerly sector, separated from that to the north by ~75 m, extends geophysically in excess of 1 km in an east-west direction. Nickel intersections have been recorded along some 500 m of the south sector, within at least four zones (E to H).
 
Ni-Cu-PGE mineralization at Dundonald South Area, was described by Houle et al. (2001), as follows: (i) stratiform contact disseminated/net textured/massive sulphides, (ii) stratabound internal disseminated, blebby, and amygdaloidal sulphides; and (iii) minor metasedimentassociated sulphides. The sulfides are composed of pyrrhotite, pentlandite, chalcopyrite, millerite, electrum and PGE alloys. Massive sulphides contain, on average, ~47.5% Ni, 0.35% Cu, and 19 g/t ∑PGE in 100% sulfides, whereas disseminated sulphides contain, on average, ~38.1% Ni, 0.88% Cu, and 24 g/t PGE in 100% sulphides.

 
Dundeal
 
The Dundeal Zone (Ni) is located on the north side of the anticline 2.2 km southeast and along strike from the old Alexo Mine. The host komatiite stratigraphy dips steeply, up to 80° to the north, tops to the north, and has been drilled over a total strike length of 2.5 km on Dundonald property.
 
Nickel sulphide mineralization occurs at the base of thick komatiitic unit apparently controlled by a channel or depression in the footwall volcanics. The Dundeal Zone has been traced along strike for 800 m and to a depth of 700 m below surface. Average true width of the mineralized interval is 2.38 m with grades up to 3.04% nickel.
 
Blebby and disseminated sulphides are the most common forms of nickel mineralization followed by occasional net textured intervals and finally as rare massive veinlets in the footwall. Pyrrhotite and pentlandite occur in sub-equal amounts along with minor chalcopyrite and rarely sphalerite. The nickel to copper ratios averaged 25:1.

 
Terminus Cu-Zn Zone
 
The Terminus Cu-Zn Zone is located ~140 m stratigraphically above the Dundeal Nickel Zone. It is hosted by a sequence of predominantly komatiitic basalt with lesser argillite and pyroxenite. The host stratigraphy is up to 56 m thick and thins rapidly to the west. Significant base metals mineralization has been outlined over a strike length of 200 m with an indicated plunge to the southeast. The mineralization occurs both as banded (bedded?) semi-massive to massive pyrrhotite with variable sphalerite and chalcopyrite, and as lower grade, disseminated to fracture controlled chalcopyrite and pyrrhotite.





Dundonald Sill Platinum Group Elements
 
Pt-Pd mineralization was discovered in the Dundonald Sill in 1991. Referred to as the "Casey's Showing", it was discovered by Falconbridge towards the end of their exploration campaign on the Dundonald property. Falconbridge reported an average of 0.63 g/t Pt+Pd over 6.0 m in a surface channel sample at this occurrence.
 
The Casey's Showing was reported by Falconbridge to be located near the lower margin of a pyroxenite layer within 7 m of the northern contact of a leucogabbro body. Pt and Pd correlate with fine interstitial chalcopyrite increasing towards the pyroxenite margin. Pt and Pd are inversely correlated, i.e., Pt values are highest in the lower 4 m while Pd values are highest in the upper 2 m. Elevated Au values (387 ppb/4 m) with no Pt-Pd association occur 4 m up-section from the Pt-Pd zone.





Three new zones of Pt-Pd mineralization discovered in 2000 and 2001, the zone receiving the most attention was the "Mighty Showing", located ~1 km northwest of Casey's Showing. The Mighty Showing was stripped and channel sampled with a diamond saw. The overall Pt-Pd zone was traced over an ~80 m strike length. It varies in width from 4.5 m to greater than 20 m. Pt-Pd values of interest were recorded over a maximum width of 11 m. The Pt-Pd zone at the Mighty Showing is contained within a pyroxenite unit where this is in contact with a thin peridotite unit. This peridotite unit represents an excellent marker horizon in this area.

 
EXPLORATION POTENTIAL
 
The lateral extent of the main Dundonald South nickel sulphide mineralization has been tested on a widely spaced diamond drill hole pattern. Diamond drilling of the Dundonald South Nickel Zones is aided by down-hole geophysics, intensive 3-D computer modeling and geological interpretation.
 
While still open at depth and along strike, FNI has begun to focus on the high grade nickel sulphide intercepts that have the greatest potential to host economic lenses. The exploration diamond drill program is designed to define the boundaries of the most prospective high grade nickel sulphide zones and provide the necessary drilling density for further evaluation.
 
At the end of this drill campaign, the management and board will review the potential to advance the project to an underground exploration program.
 
High priority geophysical targets outside of the Dundonald South and Dundeal zones will be explored on a flexible schedule as the project advances. There is excellent potential for additional high grade nickel sulphide zones given the nature of komatiite hosted nickel sulphide deposits throughout the world. The Dundonald area contains a total of four known nickel zones and 3 additional nickel showings along the komatiite trend.
 
Exploration for VMS and Pt-Pd mineralization, while not the focus, is always considered while completing the surface mapping and sampling and the diamond drill programs. All prospective units are identified and sampled during the exploration program.

Source: http://www.fnimining.com/index.php?page=dundonald