- SMDI #
- 0621
- Current Showing Name
- Collins Bay B Uranium Deposit; Collins Bay D Uranium Deposit; Collins Bay E Uranium Zone; Collins Bay F Uranium Zone
- Historical Showing Names
- Collins Bay B Uranium Deposit; Collins Bay D Uranium Deposit; Collins Bay E Uranium Zone; Collins Bay F Uranium Zone
- Company Name
- Project Name
- UTM Easting (NAD83 Z13)
- 579373.9900
- UTM Northing (NAD83 Z13)
- 6458671.1300
- NTS Sheet
- 064L05
- TRM (Township-Range-Meridian)
- 107-10-2
- Primary Commodities
- Uranium
- Associated Commodities
- Arsenic, Cobalt, Gold, Graphite, Iron, Lead, Nickel
- Discovery Type
- Status
- Deposit: Post-Production
- Geological Details
- The Collins Bay deposits (A, B, and D zones) consist of three main zones and three minor zones which are located along a 3 km (1.86 miles) interval of the Collins Bay Fault. The A Zone was located in 1971. The B Zone was drill-located 2 km (1.2 miles) to the south of the A Zone in 1976. The D Zone was located between these zones in 1979.
The B Zone, which was discovered in 1977, is a 1,000 m (3280.8 ft) long orebody located 8 km (5.0 miles) north of the Rabbit Lake Mine open Pit. The highest grade portion of the orebody is located in the footwall of the Collins Bay thrust zone within the Athabasca Group (Manitou Falls Formation sandstone) and in slivers of intensely altered basement thrust into the sandstone. The Athabasca Group unconformity overlies the granitoids. Relatively minor mineralization occurs within upthrown Aphebian pelitic graphitic gneisses of the hanging wall.
The orebody, which consists of a series of high-grade lenses separated by lower-grade zones, parallels and, for the most part, is confined to the footwall of the Collins Bay thrust zone over its entire length. The body is 915 m (3001.97 ft) long by 20 to 122 m (65.6 to 400.3 ft) wide (average of 30m or 98.4 ft). In the sandstone, the uranium occurs as intergranular fillings and as a dusting on grain boundaries. In the high grade pods and veins the mineralization is associated with alteration clays derived from basement rocks. Mineralogically, the ore consists of pitchblende coffinite, gersdorffite, nickeline, niccolite, rammelsbergite, maucherite, bravoite, violarite, skutterudite, galena, chalcopyrite, covellite, bornite, tennantite, millerite, polydimite, saffflorite, pyrite and calcite. Graphite is associated with the mineralization.
The Collins Bay area is underlain by Aphebian supracrustals, consisting of the basal pelites and semipelites of the Wollaston Group, granitoid gneisses of possible Archean age and clastic sediments of the Manitou Falls Formation (Athabasca Group). The Archean (?)-Aphebian contact dips moderately to the southeast and juxtaposes pelitic to semipelitic graphitic gneiss to the southeast against grannitoids to the southwest. Reverse faulting has taken place at the contact of the two major basement groups: - the Collins Bay Thrust Zone. The granitic gneisses are unconformably overlain by the Manitou Falls Formation.
The B Zone, like the A Zone, has a relative abundance of Ni, As and Co. To date, no significant amounts of Au or Ag mineralization have been identified in the B Zone. The B Zone open pit was mined out by February 1991. All ore was processed using the Rabbit Lake mill.
During the winter of 1979, systematic drilling encountered uranium and nickel-arsenide mineralization approximately 2600 ft (792.5 m) northeast of the B Zone. This deposit is referred to as the D Zone. The D Zone, which is morphologically, geochemically, and structurally similar to the A Zone and to the high-grade north end of the B Zone, occurs in highly altered Athabasca Group sandstones adjacent to the Collins Bay Thrust.
D Zone mineralization, which contains the same suite of ore minerals as the B Zone, consists of co-existing uranium and nickel-silver arsenides. The southwest "tail" of the deposit is relatively low in nickel-arsenides. To date, no significant amounts of Au or Ag have been found. Massive pitchblende and coffinite with gersdorfite, nickeline, and galena form an orebody which is 195 m (639.8 ft) long by 30 m (98.4 ft) wide by 24 m (78.7 ft) thick. The deposit is 91 m (298.6 ft) offshore and is covered by 7.6 m (24.9 ft) of water and 8.8 to 23.5 m (28.9 to 73.8 ft) of overburden.
The Collins Bay E Zone, which is geologically and mineralogically similar to the Collins Bay B and D zones, is a 60 m (196.9 ft) long zone of uranium mineralization located 120 m (393.7 ft) north of the north tip of the Collins Bay B Zone.
The Collins Bay F Zone, which is also geologically and mineralogically identical to the Collins B and D zones, is a <30 m (<98.4 ft) long zone of uranium mineralization located 670 m (2198.2 ft) north of the north tip of the Collins B Zone.
- Geological Domain
- Wollaston
- Host Rocks
- Host Minerals
- Arsenopyrite
- Indicators
- Exploration History
- 7/14/1988 The Collins Bay Deposits occur about 10 km (6.2 miles) northeast of the Rabbit Lake Mine. Two main zones are present along this mineralized trend which is approximately 3 km (1.86 miles) long. The B Zone was discovered in 1977 following the investigation of a number of electromagnetic conductors originating in the A Zone area. It is located approximately 2 km (1.2 miles) south of the A Zone.
Overburden stripping over the B Deposit commenced in July 1984. The first ore was fed into the mill in November 1985.
In 1989, Cameco completed HLEM surveys over the Ivison grid 2 km east of the deposits (AF 64L04-0103). Ore reserves for the B, D zones were reported.
In April 1990, Cameco sold 33.33% of it's 100.0% ownership of the deposit to Uranerz Exploration. By February of 1991, the Collins Bay B Zone pit had been mined out. The stockpile of ore contained over 5000 t U with an average grade of 0.59% U. In May 1990, ore reserves were reported for the B, D zones.
Other Work Done:
Mineralogy (Heine 1981, Jones 1980); Regional mapping (64L05-0007); Diamond drilling (diamond drill holes B75-78? 64L05-0005,0006,0007,0096,0097);
In 1993, the partners completed ground HLEM and magnetic surveys and drill holes GRAY-1, and -2 to -4 on the Grayling grid to the southeast of the B Zone deposit to probe existing anomalies (AF 64L-0022). No significant mineralzation was intersected. On 24 February 1993, revised reserves were given for the B and D zones.
In 1994, the partners involved announced that the D Zone would be mined using a 488 m (1601.0 ft) long by 122 m (400.3 ft) wide by 34 m (111.6 ft) deep open pit and the dyke to isolate the D Zone was built. The pit slopes would be 27 degrees in overburden and 34 degrees in bedrock. The pit benches would be 1.5 to 3.0 m (4.9 to 9.8 ft) in ore and 5 to 10 m (16.4 to 32.8 ft) in waste.
On 16 september 1995, it was announced that Cameco had received permission from the AECB to proceed with mining of the D Zone by open pit. Open pit mining of the D Zone commenced in the winter of 1995 to 1996. The pit was mined out in 6 months (April of 1996). 4.8 million tons of ore grading 2.00% U3O8 was recovered. The ore was mixed with A Zone ore and Eagle Point ore before being processed at the Rabbit Lake Mill.
The D Zone open pit was filled with special waste rock covered by a layer of till. The cofferdam was then opened and the remainder of the pit was flooded.
The B Zone received government approval to commence mining operations in 1982. The site was prepared for mining between 1983 and 1984. Mining of the deposit between 1985 and 1991 recovered 18,250 tons of ore which graded 0.69% U3O8. The ore was mixed with D Zone and Eagle Point ore prior to processing at the Rabbit Lake Mill. Tailings were deposited in the Rabbit Lake open pit. Decommissioning will include re-contouring, revegetation, and the planting of trees.
In 1995, a Cameco (66.6%)-Uranerz (33.3%) partnership completed drill holes GRAY-16, -16, -31, and -34 slightly south of the B Zone (AF 64L-0024). No significant mineralization was encountered.
In 1998, Cameco completed a ground TDEM and gravity on the Collins B Zone grid and drill holes GRAY-35 to -37 on the grid to the southeast of the B Zone (AF 64L04-0110). The drilling failed to intersect significant mineralization.
- Production History
- Production Period: 1996-01-01 to 1996-12-31
Cameco Corporation: D Zone (open pit)
26,395.00 tonnes
The D Zone was mined by open pit starting in the winter of 1995-1996. The ore body was mined out in 6 months and the open pit was decomissioned.
D ZONE MINE PRODUCTION FIGURES
YEAR TONNES RECOVERY MILL HEAD PRODUCTION
MILLED RATE GRADE LBS. U3O8
_________________________________________________
1996 26,395 94.1% 1.93 1,100,000
_________________________________________________
Summary:
- Uranium: 1,100,000.00 lb @ 1.93 %
Production Period: 1985-11-01 to 1991-02-01
Zone B (open pit)
18,250.00 tons
Between November 1985 and February 1991, Cameco open pit mined all B Zone ore. 18,250 tons of ore grading 0.69% U3O8 were recovered. The stockpiled ore contained 5,400 tonnes U with an average grade of 0.59% U.
Summary:
- Uranium @ 0.69 %
- Reserves and/or Resources
- 1993-01-01
B Deposit reserves: 680,000 tonnes ore grading 0.58% U3O8 (8,600,000 lb U3O8).
D Zone reserves: 116,000 tonnes ore grading 2.19% U3O8 (5,600,000 lb U3O8).
Summary:
D Zone: Historic reserve (unspecified) of 116,000.00 tonne
- Uranium: 5,600,000.00 lb @ 2.19 %
B deposit: Historic reserve (unspecified) of 680,000.00 tonne
- Uranium: 8,600,000.00 lb @ 0.58 %
1991-02-01
Summary:
Historic reserve (unspecified) of 5,400.00 tonne
- Uranium: 5,400.00 tonne @ 0.59 %
1990-05-23
Cameco Corporation – Uranerz Exploration and Mining Limited
B Zone reserves: 18,000,000 pounds U3O8 grading 0.73% uranium.
Combined A and D Zones reserves: 23,000,000 pounds U3O8 at 4.07% uranium.
Summary:
B Zone: Historic reserve (unspecified) of 18,000,000.00 lb
- Uranium: 18,000,000.00 lb @ 0.73 %
Combined A and D Zone: Historic reserve (unspecified) of 23,000,000.00 lb
- Uranium: 23,000,000.00 lb @ 4.07 %
1989-01-01
B Zone reserves: 15,769 tonnes U at an average grade of 0.61% U. The grade ranges up to 28.8% U.
D Zone reserves: 115,940 tonnes ore grading 1.66% U (2,154 tonnes U).
Summary:
D zone: Historic reserve (unspecified) of 115,940.00 tonne
- Uranium: 2.15 tonne @ 1.66 %
B zone: Historic reserve (unspecified) of 15,769.00 tonne
- Uranium: 15,769.00 tonne @ 0.61 %