Freeport Resources Ltd.Freeport Resources Ltd.

Red Rose Mine

Show printable version of 'Detailed Geology' in a New Window
Highlights  |   Detailed Geology  |   Mine Summary  |   History  |   Photo Gallery  |   Maps  |  
Media Library

Detailed Geology

The Red Rose property was primarily mined for tungsten, with an average scheelite grade of 1.5% CaWO4, generally consistent vertically throughout the mine. There are also some separate gold and silver showings at the Red Rose property. Interesting gold values in the Red Rose shear zone include an average of 19.2 grams/tonne (0.56 ounces/ton) from six samples taken in Adit #1, over a length of 49m (160').

Mineralization at the Red Rose property is related to the Lower Cretaceous Rocher Deboule stock which intrudes middle Jurassic to Lower Cretaceous siltstone and argillite of the Bowser Lake Group. Those are recrystallized into hornfels. The Rocher Deboule intrusion comprises mainly granodiorite with some diorite phases. Other rocks on the property include older Lower Cretaceous porphyritic andesite dykes, fine-grained northeasterly trending diorite dyke-like intrusive bodies and feldspar porphyry dykes younger than the diorites. The mine is almost entirely enclosed within one of the diorite intrusions, the 'Mine Diorite' (McEachern 1954). This unit is between 90-120m (300-400') wide. The second diorite intrusion is porphyritic, occurs to the south, and is about 250m (800') wide.

The Red Rose mine is located east of the north-south Chicago Creek Fault, a major regional structure. At the 800 level portal, the fault is approximately 70m (230') to the west. The Red Rose Shear zone, which strikes 30 to 40 degrees west and dips 60 to 65 degrees southwest, is a tributary to the Chicago Creek Fault.

The Red Rose mineralized vein fills the Red Rose shear zone where it cuts through the diorite, sometimes referred to as the "Mine Diorite" (after Sutherland Brown, 1960). It is composed mostly of pegmatitic quartz with lesser amounts of feldspar, biotite, hornblende, ankerite, tourmaline, apatite, scheelite, ferberite, chalcopyrite, pyrrhotite and molybdenite. The vein is massive and unsheared, with many small cavities largely filled with quartz crystals. It is 1.2 to 2.8 m wide (4-9'), for at least 60 to 120 m (200-400') along strike, and at least 335 m (1100') down dip (Minfile 093M 067). According to Brown, the tungsten-bearing vein is reportedly of mining width and grade only within the Mine Diorite.


Although the property was first prospected at the turn of the century for gold and base metals near Red Rose Creek, past exploration work concentrated mainly on the tungsten-bearing quartz vein located further up the same hillside. Historical reports indicate significant gold mineralization, particularly in Adit 1, along the Red Rose Shear, up to 2 oz per tonne. (Minister of Mines Annual Report, 1914; Telfer, 1939).

Exploratory drilling prior to the mine closure resulted in some interesting intersections suggesting another unmined ore shoot in the Red Rose shear system. One drill hole at the southern end of the 300m level intersected 3.9m (12.7') of massive pyrite and chalcopyrite replacement in sheared hornblende diorite grading 0.33% Cu, 41 g/mt (1.2 oz/t) silver and 1.9 g/mt (0.055 oz/ton) gold over 2.8m (9.1') and 0.24% Cu, 31g/mt (0.9 oz/t) Ag and 2.4g/mt (0.07oz/t) Au over the remaining 1.1m (3.6').

A two-hole drill program by Freeport intersected the Red Rose vein at the 1450 level, 100 m (328') below the lowest level (1100 level) of the mine, thus proving continuity of the vein well below the known workings, with interesting copper and molybdenum mineralization (2.7% Cu and 0.08% Mo) encountered over short intervals.

Chalcopyrite content increases with depth and constitutes some 2% of the vein filling on the lowest level. It is distributed within wall rock, sometimes with molybdenite, and within the hanging wall shear. Perkins et al. (1988) note that, "Copper mineralization increases and tungsten mineralization decreases with depth (Cu-W ratio increasing). This suggests that the same zoning pattern noted on the surface also occurs with depth. The tungsten-copper mineralization might therefore change to copper-gold mineralization at the lower levels of the Red Rose shear as seen in the old workings to the south of the mine site." This seems to be confirmed by the very high gold values found in Adit #1, near the valley floor.

Conclusion & Recommendations

The Red Rose property is highly prospective for tungsten, but its potential for gold, copper, and possibly molybdenum warrants further study. Copper-gold and silver-lead-zinc showings are known along the Red Rose shear. This structure is open to the north and south of the mine, and remains largely unexplored. High gold values within the Red Rose shear provide attractive new drilling targets. Recommended work includes:
  • Confirm historical tungsten reserves to today's standards (NI 43-101).
  • Assess the potential lateral and down dip extension of the vein by trenching and drilling, to evaluate tungsten grade as well as presence of other metals.
  • More fully explore the Red Rose shear zone for gold mineralization, both north and south of the mine.
  • Evaluate gold-rich zones with surface trenching and sampling, with follow-up drilling.
  • Geological mapping, prospecting and sampling should be an on-going process with emphasis on locating other related vein systems and types of mineralization.
  • Use current exploration techniques such as geophysics to better understand the Red Rose property.