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By W. T. Boyes, J. M. Harrison

"Squall Lake Gold Mines, Limited, owns a group of claims at Squall lake, northern Manitoba, about 75 miles east of Flin Flon and 3 to 4 miles north of the Nor-Acme mine at Snow lake. Gold mineralization was discovered in this locality several years prior to 1944, but it was only in that year that a comprehensive examination of the occurrences was begun. Development work to the end of 1946 has been encouraging and the deposits show interesting relations to rock structure.GEOLOGICAL SETTINGThe gold occurs in a sill of biotite-hornblende diorite at or near its contact with gneisses derived from arkosic sediments . In detail, the contact between the diorite and the arkose to the southeast of it is irregular, with interfingering of the two rock types. On the northwest side of the sill, between it and Squall lake, the rock is staurolite schist (see accompanying sketch-map).Several mineralized shear zones are known, of which those shown are the most important. Within the zones, the diorite is silicified and somewhat carbonatized. Fairly coarse arsenopyrite is the chief sulphide mineral in these zones but, locally, they contain also pyrite and pyrrhotite. Where quartz and chlorite are present, rather coarse gold is associated with them. In that part of the main zone where gold assays have been most consistent, the diorite is rich in albite."

Jan 1, 1954

By A. R. Kinkel JR.

"The Buffalo Ankerite mine is in the southern part of the Porcupine gold district of northern Ontario. The mine has a history of exploration and development reaching back to 1911, and has been operated continuously since 1932. From 1932 to 1942 a total of 510,874 oz. gold was produced from the mine. In 1941 the production was 71,654 oz. from 448,621 tons of ore.With few exceptions, the ore-bearing veins did not crop out. They were discovered during the prospecting of the prominent outcrops of barren or low-grade quartz-carbonate breccia near the veins.GEOLOGICAL SETTINGThe Porcupine gold district lies in an area of folded and sheared Precambrian lavas, sediments, and intrusives. The Buffalo Ankerite mine is in the southern part of a large fold. The structure appears to be a continuation of the Vipond cross anticline and accompanying syncline described in earlier papers (1, 2). The orebodies lie along both flanks of the synclinal part of the fold, and are known as the north and south vein systems, respectively. No mineable veins have been found on the axis of the syncline (Fig. 1).The rocks found in the mine area are pillow lava, dacite, conglomerate, quartz porphyry, tuff, and fragmental lava. The tuff and fragmental lava are now largely altered to chlorite schist. Productive veins have been found only in pillow lava, dacite, and conglomerate, but a minor amount of gold occurs in some of the quartz porphyry. The Porcupine Creek fault, a zone of intense shearing over 1,000 feet in width, lies immediately south of the mine. A spur fault branches to the northwest from the Porcupine Creek fault, separating the north from the south vein systems ( Fig. 1) ."

Jan 1, 1954

By T. A. Lazier, C. S. Longley

"Paymaster Consolidated Mines, Limited, owns several groups of claims in various parts of the Porcupine district. The area in which mining has been carried on includes parts of lots 5, 6, and 7, con. 1, Tisdale township, and twelve adjoining claims in Deloro township to the south. Highway No. 67A between South Porcupine and Timmins crosses the property.The discovery of the Dome mine in 1909 caused a rush of prospectors to the district and in a few weeks practically all territory adjacent to the Dome was staked. At that time work was started on the West Dome, West Dome Lake, Apex, and Standard properties. These were consolidated in 1930 to form the present Company. Gold was produced from the West Dome Lake from 1915 to 1930, and from the Standard-Paymaster from 1922 to 1928. The total production of the previous and present companies from 1915 to November 30, 1946, has been 487,170 oz. gold and 149,342 oz. silver from 2,337,554 tons of ore."

Jan 1, 1954

By M. Harrison, C. H. Stockwell

"Metals vah1ed at more than $200,000,000 have been obtained, mainly since 1930, from the mines of northern Manitoba. The greater part of this production has been copper, zinc, and gold from the Flin Flon, Sherritt Gordon, and Mandy mines. The chief mines from which gold alone has been produced are God's Lake, Laguna, and Gurney. At present (May 1947) Flin Flon and Sherritt Gordon are the only producing mines, but the Nor-Acme property is being developed for large-scale production of gold. Large deposits of nickel and copper are being diamond drilled at Lynn Lake, and the Thompson, Ferro, and other properties are being developed. The mineral deposits lie within irregular or elongated areas of Precambrian sedimentary and volcanic rocks, surrounded by granite ( Fig. 1).The common rock types include basic and acidic flows, agglomerate, ruff, greywacke, arkose, argilli te, conglomerate, and their gneissoid and schistose derivatives. They are invaded by sills, dykes, and irregular bodies of gabbro and diorite, and all are cut by granite. Some of the sediments are interstratified with volcanics, and others are deposited unconformably on them.STRUCTURAL GEOLOGYLittle is known of the structures of the rocks in the area as a whole, because by far the greater part is unexplored or has been covered only by reconnaissance surveys. Available information indicates a general east structural trend in the southeast part, whereas in the west part the folding is mote complex with no definite overall trend. However, in a few small areas in the western part where detailed work has been done, as around the Flin Flon, Sherritt-Gordon, Nor-Acme, and other properties, the structure is fairly well known. The following descriptions apply chiefly to these areas ."

Jan 1, 1954

By A. W. Johnston, R. E. Barrett

"The Central Patricia mine is in the greenstone belt north of lake Sc. Joseph in northwestern Ontario. It is 90 miles north of Allanwater on the Canadian National railway and 220 miles east of the Manitoba boundary. The unusual feature of the ore of this mine is that the gold does not occur in quartz but in sulphide minerals filling fractures in iron formation.AREAL GEOLOGYThe rocks of the area in which the mine occurs belong to the Early Precambrian. They consist · of andesite lavas and tuff interbedded with greywacke-like sediments and iron formation . A siliceous phase of the sediments lying north and south of the greywacke enclosing the ore-bearing iron formation in places resembles a sheared and sericitized quartz porphyry. This is shown in the legend of Fig. 1 as quartz porphyry and quartzite, but it is possible that the quartz porphyry-like phase is sediment. A northwest- striking dyke of diabase crosses the property 3,000 feet east of the shaft ( Fig. 1).IRON FORMATIONAlthough there are numerous bands of iron formation in the v1cm1ty of the mine, ore has been found to date in only one main and two lesser zones. The iron formation bands range in width from a few inches to 60 feet, and are interrupted along their strike by gaps that are parallel and rake to the east at about 65°. The iron formation is definitely banded and laminated."

Jan 1, 1954

By W. L. Brown

"The Normetal mine is about 7 miles east of the Ontario-Quebec boundary, and 13 miles north of the town of Dupuy on the Canadian National railway. The mine workings are largely on lots 44 and 45 in the south half of range 10, Desmeloizes township.The surface outcrop is reported to have been discovered by a trapper previous to 1925, but the details are obscure. The property was originally owned by the Canadian Exploration Company of Amos, Quebec, and was later transferred to Abana Mines, Limited. The latter Company carried out underground work from two shafts down to the 550-foot level. The property was acquired by Normetal Mining Corporation in 1931 and was reopened in 1933, when development work was carried down to the 800-foot level. The mine was closed down in 1935 because metal prices did not justify production at that time. It was reopened early in 1937 and milling commenced in September of that year. To the end of 1945, a total of 1,497,- 169 tons of ore was milled from which was produced 184,533 tons of copper concentrates containing 84,738,368 lb. copper, 2,744,100 oz. silver, 26,230 oz. gold, and 153,524 tons of zinc concentrates containing 163,752,433 lb . zinc."

Jan 1, 1954

By Victor Dolmage

"The localization of orebodies by geological structures is well demonstrated at the Copper Mountain mine of southwestern British Columbia. These extensive deposits; owned and workd by the Granby Consolidated Mining; Smelting and Power Company; are at Princeton; abo!lt 150 miles east of Vancouver and 40 miles north of the International boundary. The geology of the deposits and the surrounding district is described by the present writer in Memoir 171 of the Geological Survey of Canada; pub1ished in 1934.The main geological feature is a gabbro stock, elliptical in plan, with a major axis about 5 miles in length extending in a northwest-southeast direction. The stock varies in composition from syeno-gabbro (gabbro plus orthoclase) through diorite and syenite to a core of syenite pegmatite. All the members contain orthoclase, which ·increases greatly in amount toward the centre, but all are devoid of quartz. The stock has been injected into a steeply folded series of volcanic flows, breccias, and tuffs that strike more or less parallel with the major axis of the stock. On its northeast side the stock is flanked by a band of fairly coarse volcanic breccia of andesitic composition and ·having fragments up to several inches in length. Where this breccia is tangential to the stock it is both dynamically and chemically metamorphosed to a marked degree, and within the zone of this metamorphism are enclosed the copper deposit~. The ore consists of bornite, chalcopyrite, and a little magnetite occurring as disseminated grains and small veinlets in the metamorphosed breccias. The only gangue minerals are orthoclase, albite, oligoclase, and biotite. The two most common vein minerals, quartz and pyrite, are conspicuously rare or absent. The dynamic metamorphism has produced two well-defined structures, namely, a strong schistosity parallel with the curved vertical contact of the stock and a very striking set of small, straight, nearly parallel open fractures that stand nearly vertical and at right angles to both the schistosity and the stock contact. These are called the ore fractures."

Jan 1, 1954

By R. C. E. Bray, Peter Price

"The property of Pamour Porcupine Mines, Limited, is in the eastern Porcupine area, about 12 miles northeast of Timmins. It covers parts of lots 3-6 (inclusive), cons. 5 and 6, Whitney tp., Cochrane district, Ontario. It is an amalgamation of the old La Palme, Three Nations, and Porcupine Grande properties.The first discovery on the Pamour was made in 1911. During 1911 to 1914 a small shaft was sunk on the Three Nations vein to the 200-foot level and a 100-ton stamp mill was put in operation, but only a small production was achieved. The property remained idle from 1914 to 1923. In 1924 some diamond drilling was done along the Keewatin-Timiskaming contact with some encouraging results, but the gold mineralization encountered was too low in general at the price of gold then prevailing to warrant further · work. The increase in the price of gold revived interest in the area, and the above noted amalgamation was effected in 1934. Options were taken and successively dropped by two large mining companies. Following this, exploration both on the surface and underground was started by Quebec Gold Mining Corporation, Limited. Diamond drilling in the early part of 1933 showed considerable ore in conglomerate and greywacke to the east. In the middle of 1935 Noranda Mines, Limited, assumed control and management. A new shaft was sunk and the property was ·equipped with a mill having an initial capacity of750 tons a day. This was subsequently enlarged to 1,500 tons a day.From the commencement of milling (May 16, 1936) to the end of 1946, 5,025,545 tons of ore having an average grade of 0.1327 oz. a ton ($4.64 at $35 an oz.) have been mined and milled."

Jan 1, 1954

By W. F. James

"The property of Siscoe Gold Mines, Limited, comprises about 1,600 acres, including Siscoe island and adjacent claims under water in Montigny lake, in Dubuisson and Vassan townships, Quebec.For many years the property was reached by way of Harricana river and its chain of lakes from Amos, Quebec, about 45 miles distant. In later years a highway has been built from Noranda east through Val d'Or, about 5 miles distant.Gold was discovered on one of the claims on the north shore of Montigny lake as early as 1911, but these gold discoveries have never been economically important. Several years later gold was discovered on Siscoe island and considerable surface work was carried out. Still later, iscoe Gold Mines, Limited, was formed and carried out further work, some of it through shallow shafts. In 1928, larger scale operations were undertaken and a 100-ton mill was constructed. In the years following, production· was on a larger scale with lower grade, until finally a milling rate of over 1,000 tons a day was attained. Approximately 1,500,000 tons were treated between the end of 1940 and mid-year 1945. At present the milling rate is down to about 200 tons a day and work is confined chiefly to some of the less important veins that have been recently developed.The following is a summary of production up to December 31st, 1946:"

Jan 1, 1954

By Jas. E. Thomson

"The Kirkland Lake-Larder Lake gold area is in northeastern Ontario and is a continuation of the ore-bearing belt that extends across northwestern Quebec through the Rouyn, Cadillac, Malartic, and Bourlamaque areas. It is the oldest mining camp along this famous mineral belt. Gold discoveries were first made at Larder Lake and Swastika in 1906, but it was not until 1913 that important developments at Kirkland Lake created a real interest in the country. Total gold production of the camp passed the million dollar a year mark in 1920 and increased in amount yearly until the advent of the second World War when there was a falling off due to labour shortage. The Kirkland-Larder camp ranks as the second largest gold producing area ' in Ontario. To the end of 1944, twenty-two mines in the area had produced bullion valued at $515,631,428 and ten mines had distributed dividends amounting to $205,981,116. The average grade of the ore milled in this period has been $15.17 a ton for the mines in the Kirkland Lake area and $6.49 a ton for the mines at Larder Lake.ROCK FORMATIONS OF THE AREAIn a general way the rocks of the country may be divided into the lithological groups indicated on the accompanying geological sketch map. This map has been compiled largely from recently issued geological sheets of the Geological Branch of the Ontario Department of Minest. Owing to the present difficulty of separating the formations of the Larder Lake country into the twofold age divisions of Keewatin and Timiskaming, the usual custom in the past, a lithological grouping of formations has been adopted. The age terms 'Keewatin and 'Timiskaming' are loosely used in this article to express the often used but not necessarily accurate distinction between the main groups of older strata."

Jan 1, 1954

By A. H. Lang

"The name Barkc:rville district is applied loosely to the gold-bearing area around the historic town of Barkerville; the first mining camp in western Canada. The region is partly in the Cariboo mining division and partly in the Quesnel mining division. It contains two producing lode gold mines; the Cariboo Gold Quartz and the Island Mountain; and numerous other deposits. The regional structural pattern is outlined in this paper; the structural details of the producing mines are described in the papers that follow.The discovery of rich placer deposits in this district in 1860 was followed by the Cariboo gold rush. Placer mining in the area flourished until 1875 and then declined as the shallow diggings were exhausted, but important operations are still active. The total placer production amounts to about $50,000,000. An extraordinary number of quartz veins outcrop in the district, but many have only a small gold content. The miners soon recognized that the placer gold must have been derived from the erosion of these veins, and some directed their attention to the possibility of quartz mining. The erection of a 4stamp mill in 1876 was the first attempt at ore reduction in British Columbia, exclusive of arrastras. Efforts to mine the Cariboo lodes on a large scale were not successful, however, until 1933, when, due to the pertinacity of F. M. Wells and to the increased price of gold, the Cariboo Gold Quartz mine commenced production, followed by the Island Mountain mine in 1934. This success led to development work at many properties in the district, but the only ones that have reached production to date are the Columbia Tungstens, where scheelite has been mined intermittently since 1937, and the Cariboo Hudson, from which gold was produced in 1938 and 1939."

Jan 1, 1954

By H. C. Gunnings, C. O. Swanson

"The Sullivan mine; at Kimberley in southeastern British Columbia; is the largest silver-lead-zinc mine in the Empire and one of the largest in the world.The original discovery was made in 1892 by four prospectors. Until 1899, when the branch line of the Canadian Pacific railway from Cranbrook to Kimberley was completed, little work was done on the property. In 1900, systematic development was started, and during the next 3 years 5,000 tons of ore was shipped to the smelters at Nelson and Trail. By 1903, some 300,000 tons of ore was developed, and a smelter was started at Marysville, about 5 miles from the mine. However, this smelter closed down in 1907 because of metallurgical difficulties after treating 75,000 tons, and the property came under the control of the American Smelting and Refining Company. An option on the property was taken in 1909 by the Consolidated Mining and Smelting Company of Canada, who exercised their option in the following year. During the next 5 years by selective mining and sorting 188,000 tons of high-grade ore was produced and shipped to Trail. This tonnage came from the upper levels, about 4,600 to 4,800 feet in elevation. At the same time, deep drilling down to the 3,900-foot level showed the presence of an immense body of complex ore. In 1915, the main adit-the 3,900-foot level-was started, and by 1919 this had been driven a distance of 2 miles to develop the ore above this level. Meanwhile, progress was being made in overcoming the milling problems. An interesting account of this work was written by the staff ( 4). In 1923, the first unit of the present concentrator was erected, with a capacity of 2,500 tons a day, and thereafter the rate of production increased rapidly. In 1934 it was around 8,000 tons a day, and to date a total of about 30,000,000 tons of ore has been sent to the mill. In recent years, a considerable part of the production has come from levels between the 3,900-and 3,350-foot, which were opened by an internal incline shaft started in, 1930. In 1942, tin was added to the products separated at the concentrator."

Jan 1, 1954

By S. A. J. Hopper

"The Golden Manitou mine is in the northeast quarter of Bourlamaque township, Abitibi county, Quebec. During the summer of 1937 a body of gold-silver-zinc ore was outlined in a series of diamond drill holes located to the west of an old copper-zinc showing in the property of Quebec Manitou Mines, Limited. In 1938, a shaft was sunk and the orebody further explored from levels at depths of 210 and 360 feet.In 1941 the western half of the Quebec Manitou property was acquired by a new company, Golden Manitou Mines, Limited, and the installation of a mining and milling plant was at once undertaken. Milling started in August 1942. The following is a summary of production to December 31, 1946:The orebodies are sulphide replacements in a sericite schist shear zone. They vary in width from 8 feet to 65 feet and range in length up to 850 feet . Much of the ore is of the 'massive sulphides' type . The sulphide minerals in the ore are pyrite and sphalerite with minor quantities of .galena, tennantite, chalcopyrite, and arsenopyrite. Native silver (as wire and leaf silver) has been found in vugs and as coatings along fractures. In one section of the mine a few specks of gold were observed. Spectrographic analysis of ore samples has indicated the presence of zinc silicate."

Jan 1, 1954

By L. V. Bell

"The gold deposits of the Caribou mine are representative of those of the Province of Nova Scotia as a whole. The ore shoots within the deposits, in common with those elsewhere within the Province, are associated usually with interruptions or irregularities in the broader and uniform fold structures. The structural factors localizing ore deposition as applied more specifically to the Caribou mine are demonstrated chiefly by the close relationship of the two principal ore shoots, known as the main orebody and the 'high-grade' vein, with a pitching drag fold developed in the southeast limb of the major northeast-southwest trending anticlinal fold or elongated dome that constitutes the primary structural feature of the Caribou gold district. It is of interest to note that the evidence indicates that this drag fold, in common with other folds subsidiary to the primary fold, formed as a result of movement similar in nature to that which caused the primary fold itself. Presumably, therefore, these folds are coincident in time.The property described here as the Caribou mine is an amalgamation of two adjacent properties formerly known as the Ross and the Nova Scotia Gold, but which since 1934 have been controlled and operated as a unit by The Consolidated Mining and Smelting Company of Canada, Limited. The Caribou mine is situated in the Caribou gold district about 45 miles to the northeast of the city of Halifax and about 6 miles to the north of the Moose River gold district.The history of mining at Caribou dates back to 1867. The first recorded gold production is for 1869. From 1869 to 1933 the gold produced from the mines of the Caribou district aggregated 47,249 oz. from 93,234 tons of ore treated. The grade of the ore on the basis of the gold actually recovered from the district would thus average 72 oz. gold a ton, which, as will be noted from the following, is precisely the grade of the ore treated from the Caribou mine during operations by The Consolidated Mining and Smelting Company. These operations commenced in September, 1934, and milling on a commercial basis was under way during 1938. Since that time production, apart from a short period in 1945 during which efforts were concentrated on development work, was continuous to early in 1947, when the mine closed down owing to exhaustion of the known orebodies. Gold produced from the Caribou mine by The Consolidated Mining and Smelting Company from September, 1934, to the close of 1946 aggregated 43,205 oz. from 90,754 tons of ore milled; the grade of ore treated averaged 0.50 oz. gold a ton. The indicated average grade of O.S oz. gold a ton for the ore of the Caribou district throughout its mining history ranks somewhat higher than the 0.37 oz. a ton average for the ore milled to date from the several gold districts throughout the Province as a whole according to the production statistics of the Provincial Department of Mines."

Jan 1, 1954

By E. G. Langille

"The Premier mine; owned by Silbak Premier Mines; Limited; is 14 miles from Stewart at the head of Portland canal. Development of the property began in 1918; and since chat time a very large amount of gold and silver as well as some lead and copper have been produced from the mine.The area in the vicinity of the mine is underlain by greenstones tuffs, and sediments of Mesozoic age, belonging to the Bear River formation of the Hazelton group. These rocks are intruded by a stock 2 miles in diameter, composed of orthoclase porphyry and called the Premier porphyry. It sends numerous sill-like and dyke-like tongues into the Bear River formation, and is intruded in turn by a granodiorite outlier of the Coast Range batholith. The orebodies occupy fractures and fracture or shear zones. Primary ore consists chiefly of pyrite, galena, and sphalerite, with some chalcopyrite. The upper 300 feet, or locally 600 feet, contained presumably secondary silver minerals."

Jan 1, 1954

By J. B. Mawdsley

"The Red Lake Gold Shore mine is 4/5 mile west of the town of Red Lake, Ontario, and a mile northwest of the Howey mine. It came into production in August 1936, and in a little over 2 years produced 21,099.58 oz. gold from 83,949 tons milled.An investigation of this deposit was made by the writer during parts of September and October, 1937t. The geology of the deposit is also discussed by H. C. Horwood(2) , and the characteristics of the ore were investigated by the Bureau of Mines, Ottawa (1).The orebodies are pipe like and close together, in a north-northwesterly trending zone of dykes, veins, and shear zones in a granodiorite stock, just south of a pronounced valley with a trend of N.65°E. believed to lie along a strong shear zone and fault . The dykes, veins, and mineralization are believed to have been successively emplaced along structures having three general trends and that were due to compressive stresses that alternated, at least four times, from west of north to east of north. In common with many other gold deposits, the gold mineralization here occurred late and followed the last east-of-north stresses.WALL-ROCKSThe mine is within the Dome stock, % mile from its southeast margin. Near the mine the rock is a pink hornblende-biotite granodiorite, grading within short distances, but not abruptly, into a dark grey variety. Near the workings at least, scattered small inclusions form about ½ to 5 per cent of this body. Most of them are fine-grained, angular, or partly rounded, greenstone fragments, but some have been partly granitized and feldspar has been developed in them."

Jan 1, 1954

By C. C. Allen, H. H. North

"The Young-Davidson mine is in the southeastern part of Powell township, in the district of Matachewan. It is 32 miles southwest of Kirkland Lake, 48 miles southeast of Timmins, and 25 miles by road Northwest of Elk Lake. The Young-Davidson and its neighbour, the Matachewan Consolidated mine, are the two present producing properties in the district. The Matachewan area is the southwestern extension of the Kirkland Lake belt or 'break'. The Young-Davidson mine since coming into production in 1934 has been operated by Hollinger Consolidated Gold Mines, Limited. ""Desultory prospecting(1) has been carried on in the Matachewan area from time to time since the discovery in 1906 of silver in James township at Elk Lake, and some gold has been found in the southeastern part of Alma township and in the central part of Cairo township. The first real interest in the area, however, was started by Jake Davidson's discovery in 1916 of gold on Davidson creek, on what is now part of the Young-Davidson property, and by Sam Otisse's discovery shortly afterwards on claims a short distance to the east, now part of the Matachewan Consolidated property. In subsequent years both of these properties were investigated by various companies; the Young-Davidson chiefly by the Porcupine Gold fields Development and Finance Company, Limited, and the Matachewan Canadian by the Colorado-Ontario Development Company, Limited, which in 1919 was reorganized under the name of Matachewan Gold Mines, Limited. Work was discontinued as the ore was considered too low in grade to be mined"". However, in 1933 Hollinger Consolidated Gold Mines, Limited, undertook to bring the property into production and this became a reality in 1934.The total production to the end of year 1945 was 319,185.59 oz. gold and 73,541.94 oz. silver from 3,228,845 tons of ore. This represents an average grade of $3.67, including exchange and premiums."

Jan 1, 1954

By Russell McIntosh

"The Madsen mine is in the southeastern part of Baird township, in Red Lake area, Ontario. It lies about 6 miles southwest of the town of Red Lake, with which it is connected by an all-weather road.The Madsen Red Lake Gold Mines Company was formed in March, 1935, to take over the holdings of the Falcon Gold and Jomac Gold syndicates. During 1935 an4 the early part of 1936 No. 1 shaft was sunk and drifts driven on four levels, all on a narrow quartz vein in a granite dyke.In July, 1936, the Austin zone was discovered about half a mile north of No. 1 shaft by Austin McVeigh, a prospector employed by the Company. Diamond drilling showed that the zone included an orebody worth development, and in 1937 No. 2 shaft was sunk, three levels opened up and sufficient ore outlined to justify the installation of a mill. Milling commenced in August, 1938, at the rate of 300 tons a day, which was later increased to 400 tons a day.The total production from 1938 to 1946 was 1,116,307 tons from which gold and silver having a value of $9,949,010 were recovered. The gold produced ranged from a minimum of 0.1910 oz. a ton in 1939 to a maximum of 0.2827 oz. in 1944. The average grade in 1946 was 0.2345 oz. to the ton."

Jan 1, 1954

By R. A. Halet

"The Malartic Gold Fields mine is a good example of the association of ore deposits with a major fault zone. It also exemplifies the control exerted by the physical and chemical character of the host rocks on the localization of orebodies.The mine is in Fourniere and Dubuisson townships, Abitibi county. It is 6 miles east of the town of Malartic, 9n the main highway and railway from Noranda to Val d'Or.The discovery of the mine is due largely to the enterprise of the late J. P. Norrie, who organized the present Company in 1935. The ground is entirely covered by overburden, but Mr. Norrie believed that the extension of the Cadillac-Malartic 'break', the principal ore-bearing structure of the district, would be found on this group of claims. This belief was supported by the discovery of gold-bearing float in the area, and was confirmed by a dip-needle survey and a few pilot diamond drill holes that showed that the favourable Malartic greenstone band passes through the centre of the property.In this way the most favourable area for prospecting was narrowed to a zone 2 ½ miles long by ½ mile wide underlain' by greenstone. The remainder of the property is underlain by sedimentary rocks, which, from experience elsewhere in the camp, were not considered as promising. However, as the entire surface is covered by deep overburden, the location of orebodies even within this more or less restricted area could be accomplished only by a long campaign of diamond drilling. Systematic diamond drilling began in 1936.The contacts of the greenstone band were considered to be the most promising places to begin the work, and the early drilling was concentrated on the south contact, because the orebody of the East Malartic mine, 4 miles to the west, had been discovered on this structure and it was reasonable to hope for a repetition of these conditions. Although the south contact was very thoroughly explored, with a certain amount of encouragement, the work did not prove the existence of deposits of ore grade, and attention was shifted to the north contact zone of the greenstone band. In this locality much more promising results were obtained, and a number of good orebodies were outlined."

Jan 1, 1954

By Robert A. Brown

"The O'Brien mine is in the west-central part of Cadillac township along the Cadillac 'break', which extends for 7,500 feet from west to east across the property.The ground was staked in 1924 by A. Dumont and W. Hermeston, prospecting for M. J. O'Brien, Limited. The first vein discovered is that now known as No. 1. The No. 4 vein was later exposed on the surface; the other veins known to be present were revealed by underground work and diamond drilling carried out both from the surface and underground.The mine is developed from three vertical shafts: No .. 2 extending from the surface to 2,000 feet; No. 3 from the surface to 1,500 feet; and No. 4 from 2,000 to 3,000 feet. There is on the property a mill of about 200 tons a day capacity, the usual shops, and a townsite housing about forty-five families. Gold production to the end of September, 1944, amounted to 295,824 fine oz. from ore having an average grade of 0.505 oz. a ton. In addition, the mill recovered 3,237 tons of arsenic trioxide having a purity of 83 per cent As2O3.GENERAL GEOLOGYThe four main groups of rocks of the Cadillac area- the Cadillac, Blake River, Kewagama or Pontiac, and Malartic- are found within the boundaries of the property. However, as these rocks have been fully described in · various government reports (1,2,3,4,5,6) and all the known orebodies occur within one group- the Blake River-a detailed description of the geology will be dispensed with here. The known ore deposits lie south of the Cadillac 'break' in a group of rocks that includes 'greenstones', greywackes, conglomerate, porphyries, and a rock of gabbroic composition that may be intrusive. Both flows and tuffs can be recognized in the 'greenstones'. The two bands of porphyry that trend easterly across most of the property have been considered by some observers to be dyke rocks and by others to be flows. Certain evidence points to their being dykes that were intruded as sills considerably prior to the emplacement of the gold-bearing veins, but the possibility of flow origin cannot be fully rejected. North of the talc-chlorite-carbonate schist zone forming the 'break' the rocks are conglomerate and greywacke with iron formation, in which there are no known veins of ore grade. Within the schist zone are minor acid and basic intrusives. The general trend of both bedding and schistosity is a few degrees south of east. The dip is generally vertica1 or steep to the south."

Jan 1, 1954