Cathroy Larder (Mirado)

Location: McElroy Township
Years of Operation: 1941 – 1944, 1947, 1957, 1987
Tons Milled: 89,719
Ounces of Gold Produced: 10,231







Cathroy Larder Mine (Past Producer)

Partial history as of 1979


Au, Ag


Approximately 7^ miles southwest of Larder  Lake village, adjacent to the 3-mile post on the McElroy-Catharine township boundary, in southern McElroy  Township  and  northern  Catharine Town ship.  Shaft  in  patented  claim  L26272.  Latitude 48.020 , Longitude 79.830 . Map reference: ODM 1950-3, Township of McElroy, and portion of Township of Boston.


Keewatin intermediate to felsic metavolcan ics (mainly fragmental rocks, some rhyolite), striking N700W  and  dipping  north,  are  intruded  by  small dikes of syenite porphyry, diorite, and lamprophyre. In the vicinity of the shaft, several  shear zones par allel the trend of the metavolcanics. The ore zones mined by Yama Gold  Mines Limited in  the  shaft  area  occurred  as  a  series  of  roughly parallel  mineralized  zones  in  moderately  schistose fragmental  metavolcanics.  Each  zone  consisted  of several  narrow  fractures  heavily  mineralized  with gold-bearing sulphides. The  zone  mined  by Cathroy  Larder Mines Limited consisted  of  seams  and  irregular  masses  of  gold- bearing  sulphides  (pyrite  with  some  chalcopyrite and  sphalerite)  in  highly  altered  and  sheared  frag mental metavolcanics.


Diamond-drilling  in  1964 indicated  ore  reserves  of  435,000  tons  averaging 0.23 ounce  of Au per ton  (Northern Miner, March 14,  1968; January 24,  1971). An estimate  made  in 1972  placed ore reserves at 650,000 tons averaging 0.204 ounce of Au per ton (Northern Miner, August 31,1972).


Royado  Mines  Limited  (subsidiary  of Mirado Nickel Mines Limited).


1915:  Property  initially  staked  by  E.R. Ostrom.
1918-1933:  Unspecified  work  by  a  number  of operators.
1937-1943:  Considerable  surface  trenching  and diamond-drilling.  Shaft  to  528  feet  with  lateral development  on  levels  at  125,  250,  375,  and  500 feet.  Small  amounts  of  production  from  50-ton test  mill  during  the  period  1941-1943.  All  work by Yama Gold Mines Limited. 1943
1948:  15,000 feet of surface diamond-drilling outlined  a  new gold-bearing zone in claim  L24690. This  resulted  in  11,620 feet of lateral development and  at  least  12,000  feet of underground diamond- drilling,  mainly  on  the  250-  and  500-foot  levels. Production  during  1944  and  1947.  All  work  by Cathroy Larder Mines Limited.
1957:  Small  amount  of  production  by  Cathroy Larder Mines Limited.
1961: Extensive program of surface and underground diamond-drilling  by  Mirado  Nickel  Mines  Limited who  had  optioned  and  subsequently  bought  the property.
1963:  16  diamond-drill  holes  (15,373  feet)  by Broulan Reef Mines Limited.
1964: Surface work by Mirado Nickel Mines Limited.


Years Gold Silver Ore Milled Recovered Grade
 (ounces) (ounces)  (tons)  (ounce of Au per ton)
1947, 1957
3,227 993 22,250 0.15


Northern  Miner,  March  14,  1968; January 24, 1971; August 31, 1972.
ODM 1950, Vol.59, pt.6, p.39-44.
ODM 1964, MRC3, p.20-21.
Resident  Geologist’s  Files,  Ontario  Ministry  of Natural  Resources,  Kirkland Lake:
McElroy Town ship,  Johnston  (1947-1948),  Keating  (1948)  and others.

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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