Abstract 1991 MAY 31 FRIDAY MORNING tour underground at Macassa. From the Bon Air Motel, proceed 5.85 km west along Highway 66 (Government Road) then turn right; at 6.85 km park near Macassa No.3 shaft headframe. For a description see paper entitled “Macassa Mine Geology” in this guidebook.

Abstract The Macassa Mine, a division of LAC Minerals Ltd. is situated immediately west of the town of Kirkland Lake, Ontario. It is the only active producer of seven (7) mines located along the famed Mile of Gold in the Kirkland Lake Gold Camp. Production from all seven mines in the camp from inception to the end of 1989 amounted to 52.6 million tons generating 23.4 million ounces at an average grade of 0. 446 ounce/ton (source: MNDM resident geologists office pers. comm. ). Production at the Macassa Mine commenced in late 1933 at a rate of 200 tons per day. The mine has produced gold continuously for the past 58 years. In May 1990, the Macassa Mine produced its 3 millionth ounce. Total mine production to the end of 1990 amounts to 6,835,110 tons mined yielding 3,070,502 million ounces of gold at an average grade of 0. 45 ounce/ton. The cut-off grade at the mine is 0.25 ounce/ton. Current proven and probable ore reserves are estimated as of January 1991 to be 1. 67 million tons at a grade of 0. 53 ounce/ton. Current underground production is on the order of 550 tons per day. The Kirkland Lake Gold Camp is situated on the southwestern portion of the Abitibi greenstone belt (Fig. 1). On a smaller scale, the Kirkland Lake area can be considered as a series of volcanic, sedimentary and intrusive litho-units which strike N 60–80 E and dip steeply to the- south. These litho units which lie within the Timiskaming group are wrapped around both the Lebel Stock and Round Lake Batholith situated to the south.

Abstract The trip begins in Toronto (1991 May 30 Thursday) and proceeds to Kirkland Lake by motor coach. The evening includes a Kirkland Lake branch CIM meeting (speaker Wayne Benham on a recent Kirkland Lake gold discovery by Battle Mountain Canada Incorporated) and an introduction to the Macassa Mine geology by D. F. Cater.

Abstract The trip begins in Toronto (1991 May 30 Thursday) and proceeds to Kirkland Lake by motor coach. The evening includes a Kirkland Lake branch CIM meeting (speaker Wayne Benham on a recent Kirkland Lake gold discovery by Battle Mountain Canada Incorporated) and an introduction to the Macassa Mine geology by D. F. Cater.

Abstract The trip begins in Toronto (1991 May 30 Thursday) and proceeds to Kirkland Lake by motor coach. The evening includes a Kirkland Lake branch CIM meeting (speaker Wayne Benham on a recent Kirkland Lake gold discovery by Battle Mountain Canada Incorporated) and an introduction to the Macassa Mine geology by D. F. Cater.

Abstract The trip begins in Toronto (1991 May 30 Thursday) and proceeds to Kirkland Lake by motor coach. The evening includes a Kirkland Lake branch CIM meeting (speaker Wayne Benham on a recent Kirkland Lake gold discovery by Battle Mountain Canada Incorporated) and an introduction to the Macassa Mine geology by D. F. Cater.

Abstract The AFTERNOON tour will be by bus, the first 4 stops being in the 10 × 10 km geographic township of Teck, and the 5th is in Lebel, the adjoining Township to the east. From Macassa No.3 shaft return to Highway 66, turn right (west) along Highway 66 past Highway 112 junction and beyond the cemetery, then turn left into the Kirkland Lake Core Library of the Ontario Ministry of Northern Development and Mines. 8. 4 km. STOP 1. Here at the Core Library, standard Archean sections of diamond drill core and hand samples will be laid out for your perusal. The sections will comprise komatiitic, tholeiitic, calc-alkalic, and alkalic volcanic extrusi ves, and several types of sedimentary rocks. From the parking lot of the Core Library, turn right onto Highway 66 and proceed to 13. 0 km, where you turn left (north) along Oakes Avenue and park in the circle directly to the left. 13. 2 km. STOP 2. Kirkland Lake “Museum of Northern History”. Formerly the museum was the home of Sir Harry Oakes, one of the few prospectors who retained control of the mine he found, the famous Lake Shore that produced more than 8 1/2 million ounces of gold and almost 2 million ounces of silver. During your one hour stay, you can see relics of the early days of Kirkland Lake gold mining. From the museum we will walk across Highway 66 and up hill along a water line to a series of outcrops beginning south of the Don Lou Motel, near the base of the former water tower of the Lake Shore mine.