Location: Midlothian Township
Years of Operation: 1965 – 1966
Tons Milled: 15,835
Ounces of Gold Produced: 3,573






Stairs Mine (Past Producer)


Au, Ag


Approximately  19  miles west  of  Matachewan,  immediately  northeast  of  Frank  Lake,  in northwestern  Midlothian  Township.  Shaft  on boundary  between  claims  MR26663  and  MR 26665. Latitude 47.900 ,  Longitude 81.060 . Map  reference:  ODM  2187,  Halliday  and  Midlo thian Townships.


The  mine  is  located  on the southern edge of  a  belt  of  steeply  dipping  Timiskaming  meta sediments  (conglomerate,  greywacke,  arkose,  slate, and  green  carbonate  rocks)  which  disconformably overlie  Keewatin  metavolcanics  (rhyolite  and rhyolite breccia). The  ore  zone  is  confined  to the  trough of a west ward-plunging  right-lateral  drag  fold  on  the  south limb of  an  east-plunging  syncline.  The  drag-folded metavolcanic-metasedimentary contact trends N800W and dips steeply north. Gold-bearing quartz veins  emanate  from  the  hanging  wall  of  a  unit of unsheared  rhyolite  breccia and form tight fracture- fillings  in  a  northeast-trending  shear  zone  which intersects the trough of the plunging drag fold. The  ‘A’  Zone  consists of the  Pope  Vein  and  two subsidiary  veins,  the  Marcasite and Chromic Veins. The  Pope  Vein strikes N550E, dips 750NW,  is  1  to 2 feet in width, and consists of chalcopyrite, sphal erite,  galena,  tetrahedrite,  gold,  and  gold-silver electrum  in  a  gangue  of  quartz,  calcite,  siderite, and  sericite.  The  10-inch  wide  Marcasite  Vein  is subparallel  to  the  Pope Vein and merges with it at depth. The 6-inch wide Chromic Vein  has not been mined.


Assays of samples from sur face  trenches  mainly  ranged  from  trace  to  0.14 ounce  of  Au  per  ton.  There  were  several  high values,  including  one  of 55  ounces  of Au per ton. Reserves,  to the 500 foot level, of proven and probable  ore  are  45,200  tons averaging 0.88 ounce of Au  per  ton  and  95,700  tons  averaging 0.25 ounce of Au per ton.


Leased  by  Stairs  Exploration  and  Min ing Company Limited.


1944-1945:  Prospecting  and  trenching  by Upper Canada Mines Limited.
1947:  Geological  survey  by  Sherwood  Gold Mines Limited.
Circa  1956:  12  diamond-drill  holes  (470  feet)  by Anderson and Clark.
1959:  Six  diamond-drill  holes  (551  feet)  by  l.C. Stairs.
1962:  Airborne  geophysical  survey  and  prospect ing.  Surface  diamond-drilling  indicated  gold-filled fracture  zone. Adit (inclined 200 )  to vertical depth of  100  feet  and  some  crosscutting  and  horizontal adit of unknown  length. Shaft to 700 feet, levels at 80, 200, 350, 500 and 650 feet, 7,391 feet of under ground  development,  7,647  feet  of  underground diamond-drilling,  and  35,729  feet  of  surface  dia mond-drilling.  A  50-  to  75-ton  mill  was  installed underground  on  the  80-foot  level.  Production dur ing  1965 and  1966. All work by Stairs Exploration and Mining Company Limited.
1966:  Mine closed and program to investigate several  conductive  zones  (indicated  by  1963  airborne geophysical  survey)  by  Stairs  Exploration  and Mining Company Limited.
1968: Mine equipment sold.
1973:  Option  agreement  with  Conmont  Mining Properties Limited.


Year Gold Silver Ore Milled Recovered Grade
(ounces)  (ounces)  (tons) (ounce of Au per ton)
1965-1966 3,573 1,767 15,835 0.23


ODM  1947,  Vol.56,  pt.5,  p.20  (Sher wood Gold Mines Limited).
ODM 1970, GR79, p.23-29.
Resident  Geologist’s  Files,  Ontario Ministry of Na tural  Resources,  Kirkland  Lake:
Midlothian Town ship, Stairs Exploration and Mining Co.

Gordon, J.B., Lovell, H.L., de Grijs, Jan, and Davie, R.F.
1979:  Gold  Deposits of Ontario,  Part  2:  Part of District of Cochrane,  Districts of Muskoka,  Nipissing,  Parry  Sound,  Sudbury,  Timiskaming,  and  Counties  of Southern  Ontario;  Ontario  Geological  Survey,  Mineral  Deposits  Circular  18,  253p.

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