Ontario Mineral Inventory

Ontario Geological Survey
Permanent Link to this Record: MDI52H13NE00009

Record: MDI52H13NE00009

General

Mineral Record Identification
Record Name(s)	Chrome Lake Mine - 1930, Obonga Lake Chrome - 1994, Chromium Mining and Smelting Corp. - 9999
Related Record Type	Simple
Related Record(s)
Record Status	Developed Prospect With Reported Reserves or Resources
Date Created	1991-Mar-26
Date Last Modified	2023-Oct-18
Created By
Revised By

Commodities

Primary Commodities: Chromium

Location

Township or Area: Obonga Lake Area, Puddy Lake Area

Latitude: 49° 58' 11.91" Longitude: -89° 29' 24.08"

UTM Zone: 16 Easting: 321446 Northing: 5538264 UTM Datum: NAD83

Resident Geologist District: Thunder Bay South

NTS Grid: 52H13NE, 52H14NW

Point Location Description: Development rock pile adjacent to shaft

Location Method: Field Visit with GPS

Access Description: Highway 527 is located approximately 25 km east of the Chrome Lake Mine site. Recent logging activity has created logging access roads to within 3.5 km of Chrome Lake. The logging road access route is via the Obonga Lake Road which intersects Highway 527 approximately 30 km south of Armstrong.

Exploration History

1928: An occurrence of chromite was observed by W.K. Keefe and R.A. MacDonald. They staked the occurrence and transferred ownership to Golden Centre Mines Inc. of New York. 1930: Consolidated Chromium Corporation, a subsidiary of Golden Centre Mines, was organized to develop the property. Development work, consisting of stripping, trenching and drilling was conducted. A shaft was sunk to a depth of 350 feet, with levels at 100 and 225 feet. Operations ceased in late fall when Charles V. Bob Company of New York, owner of Golden Centre Mines Inc., collapsed. Ownership of the property was not protected. 1932: Chromium Alloy Company Ltd. was incorporated and gained control of the property. 1933: Chromium Alloy Co. sent 70 tons of ore to Niagara Falls, New York for beneficiation tests. 1934: Chromium Mining and Smelting Corp. Ltd. was formed and took control of the property. Twenty-three holes were drilled totalling 5,000 feet. Reserves for the 'E' zone of 225,000 tons averaging 17% Cr2O3 were indicated over a strike-length of 770 feet to a depth of 300 feet (Chromium Mining and Smelting Corp. Ltd., Annual Report (1935). 1936: Mining operations re-commenced. A 50 ton concentrator was constructed on the property. Mining resumed on the existing levels and on a new 325 foot level. 1937: Underground work was discontinued due to poor ore recovery. A Cr/Fe ratio of less than 1:1 was produced in the concentrate and earlier ore reserves were disproved. 1938: Operations ceased after minimal surface and underground drilling. 1974: The property remained idle until Chromium Mining and Smelting Corp., Ltd. merged with two companies to form Chromasco Ltd. 1986: Chromasco Ltd. re-organized and became Timminco Metals, a division of Timminco Ltd. 2014: prospecting and bedrock geochemistry survey by Pavey Ark Minerals Inc.

Assessment Work on File

Assessment Work on File
Office File Number	Online Assessment File Identifier	Online Assessment File Directory
63.6077	52H14NW0002	52H14NW0002

Geology

Province: Superior

Subprovince: Wabigoon

Belt: Obonga Lake

Geological Age: Archean

Geology Comments

Dec 07, 2005 (B Schnieders) - The serpentinized ultramafic intrusion at Puddy and Chrome Lakes is exposed for 7 km along strike and is approximately 1 km in width. The ultramafic intrusion is emplaced at the contact between Archean quarzofeldspathic paragneiss and Archean volcanogenic metasediments. The center of the intrusion exhibits a weak foliation which becomes intensified towards its northern and southern contacts. Scattered occurrences of of relict olivine-pyroxene cumulate textures, together with petrography, indicate primary dunitic and peridotitic compositions (Whittaker, 1979 MP 90 OGS, 1986). The occurrences occur as serpentine lenses with small chromite grains. The weathered surface of serpentine is largely black or rusty in colour. Chemical analyses showed a variation between 27 and 34 percent Cr2O3 (Graham, 1931; Resident geologist's Files, Thunder Bay). Chromite deposits are associated with the lenticular mass of serpentine that extends from the west end of Puddy Lake to a point 1 1/2 miles east of Chrome Lake, a distance of 3 1/2 miles. Chromite mineralization occurs in three forms: layered, disseminated and podiform (Johnson and Bloomberg, Assessment Files, Thunder Bay). The chromite appears to have been an original constituent of the peridotite, and its concentration into the types of deposits described is believed to have been due to processes of segregation that went on simultaneously in widely seperated parts of the peridotite body during the period of cooling and crystalliztion. The chromite occurs in disseminated grains, small podiform masses, schlieren-type aggregates and discontinuous layers in a serpentinized ultramafic lens (Watkinson and Mainwarning, 1979 MP 87, OGS). Layered chromite is best exposed at the north end of Chrome Lake where the layered zone is approximately 0.5 m thick, strikes north and dips easterly. The layers vary from 1 cm to 6 cm thick and are cumulate concentrations of medium grained subhedral chromite (Whittaker, 1979, MP90 OGS).

Dec 07, 2005 (R Degagne) - Whittaker (1986) describes the geology as follows: The serpentinized ultramafic intrusion at Puddy and Chrome Lakes is exposed for 7 km along strike and is approximately 1 km in width. The intrusive body is emplaced at the contact between Archean quartzofeldspathic paragneisses and Archean volcanogenic metasediments. A stock of porphyritic quartz monzonite, intruding both paragneiss and the metasediments, forms part of the southwest contact. Magnetic data indicate a southerly dip. Rocks of the intrusion include dunite, peridotite, and minor pyroxenite, all of which are serpentinized. North-striking and east-striking dikes of probable Late Precambrian age cut the intrusion. Faulting, indicated by intense shearing of the ultramafic rocks, is evident at the west end of Puddy Lake and at the north end of Chrome Lake. Country rock xenoliths of paragneiss occur along the north contact of the intrusion at Puddy Lake. The xenoliths are elongate slabs aligned parallel to the contact. Johnson and Blomberg (Assessment Files, Thunder Bay) describe the mineralogy of the property. Chromite mineralisation occurs in three forms: layered; disseminated and podiform. Disseminated chromite is the most widely distributed style of chromite mineralisation and it occurs along with layered and massive chromite (>75 percent chromite). Chromite, in disseminated form, is very fine grained and forms 5 to 15 percent of the serpentinite. At the north end of Chrome Lake, disseminated chromite has been redistributed by shearing into wispy schlieren-type concentrations 0.2 inches thick and up to 1.5 inches long, separated by black-green, strongly foliated serpentinite. Chromite in layered form is also best exposed at the north end of Chrome Lake where the layered zone is approximately 1.6 feet thick, strikes north, and dips easterly. The layers are deflected to a northwesterly strike as an east-striking fault contact with the paragneisses to the north is approached.

Lithology

Lithology Data
Rock Type	Rank	Composition	Texture	Relationship
Paragneiss	1	Quartzofeldspathic		Adjacent
Terrigenous-Clastic-Unsubdivided	2	Volcanogenic Metasediments		Adjacent
Dunite	3	Dunite	Serpentinized	Host
Peridotite	4	Peridotite	Serpentinized	Host
Pyroxenite	5	Pyroxinite	Serpentinized	Host

Lithology Comments

Dec 07, 2005 (R Degagne) - Rocks of the intrusion include dunite, peridotite, and minor pyroxenite, all of which are serpentinized. North-striking and east-striking dikes of probable Late Precambrian age cut the intrusion. Faulting, indicated by intense shearing of theultramafic rocks, is evident at the west end of Puddy Lake and at the north end of Chrome Lake. Country rock xenoliths of paragneiss occur along the north contact of the intrusion at Puddy Lake. The xenoliths are elongate slabs aligned parallel to the contact.

Mineralization

Mineralization and Alteration
Rank	Mineral Name	Class	Economic Mineral Type	Alteration Mineral Type	Alteration Ranking	Alteration Intensity	Alteration Style
1	Chromite	Economic	Ore
1	Serpentine	Economic	Gangue
	Serpentine	Alteration		Serpentinization	1	Strong	Disseminated

Mineralization Comments

Dec 07, 2005 (R Degagne) - Johnson and Blomberg (Ass. files, T. Bay) describe the mineralogy: Chromite mineralisation occurs in three forms: layered; disseminated and podiform. Disseminated chromite is the most widely distributed style and it occurs along with layered and massive chromite (>75 percent chromite). Chromite, in disseminated form, is very fine grained and forms 5 to 15 percent of the serpentinite. At the north end of Chrome Lake, disseminated chromite has been redistributed by shearing into wispy schlieren-type concentrations 0.2 inches thick and up to 1.5 inches long, separated by black-green, strongly foliated serpentinite. Chromite in layered form is also best exposed at the north end of Chrome Lake where the layered zone is approximately 1.6 feet thick, strikes north, and dips easterly. The layers are deflected to a northwesterly strike as an east-striking fault contact with the paragneisses to the north is approached. Individual chromite layers vary from 0.4 inches to 2.3 inches thick and consist of cumulate concentrations of fine- to medium-grained subhedral chromite. Geochemical Data From OFR 5889: Sample 1 Serpn. 35.10 SiO2, 4.51 Al2O3, 18.60 Fe2O3, 23.20 MgO, 3.10 CaO, 0.19 MnO, 0.38 K2O, 0.04 P2O5, 3.48 Cr2O3, 0.28 Na2O, 0.23 TiO2. Sample 2 Serpn. 33.10 SiO2, 1.37 Al2O3, 12.00 Fe2O3, 33.80 MgO, 1.11 CaO, 0.14 MnO, 0.04 K2O, 0.02 P2O5, 2.90 Cr2O3, 0.01 Na2O, 0.09 TiO2. Sample 3 Serpn. 34.90 SiO2, 1.26 Al2O3, 11.10 Fe2O3, 34.40 MgO, 0.80 CaO, 0.14 MnO, 0.07 K2O, 0.02 P2O5, 1.48 Cr2O3, 0.10 Na2O, 0.06 TiO2. Sample 4 Serpn. 28.00 SiO2, 15.90 Al2O3, 18.80 Fe2O3, 23.80 MgO, 0.44 CaO, 0.15 MnO, <0.01 K2O, 0.11 P2O5, 0.25 Cr2O3, <0.0 Na2O, 1.47 TiO2. Sample 5 Serpn. 26.30 SiO2, 5.46 Al2O3, 14.20 Fe2O3, 24.40 MgO, 2.04 CaO, 0.31 MnO, <0.010 K2O, .02 P2O5, 16.80 Cr2O3, 0.01 Na2O, 0.30 TiO2. Sample 6 Serpn. 49.10 SiO2, 11.40 Al2O3, 10.90 Fe2O3, 12.00 MgO, 7.30 CaO, 0.21 MnO, 0.89 K2O, 0.06 P2O5, 1.08 Cr2O3, 1.34 Na2O, 0.47 TiO2.

Mineral Record Details

Classification
Rank	Classification
1	Mafic-Ultramafic Intrusion
2	Magmatic

Characteristics
Rank	Characteristic
1	Layered

Mineral Zones - Size and Shape

Rank: 1 Structure Type: Shear

Zone Name: Detour Lake - Rank 1
Shape	Length	Thickness	Depth	Strike	Dip	Plunge	Trend	Age	Reference
Irregular			137	90	35

Zone Name: Detour Lake - Rank 1
Shape	Length	Thickness	Depth	Strike	Dip	Plunge	Trend	Age	Reference
Tabular			.6

Zone Name: Detour Lake - Rank 1
Shape	Length	Thickness	Depth	Strike	Dip	Plunge	Trend	Age	Reference
Tabular

Zone Name: Detour Lake - Rank 1
Shape	Length	Thickness	Depth	Strike	Dip	Plunge	Trend	Age	Reference
Irregular

Zone Name: Detour Lake - Rank 1
Shape	Length	Thickness	Depth	Strike	Dip	Plunge	Trend	Age	Reference
Irregular	305	180

Zone Name: Detour Lake - Rank 1
Shape	Length	Thickness	Depth	Strike	Dip	Plunge	Trend	Age	Reference
Irregular

Site Visit Information

Date: Dec 12, 1996

Geologist: R Degagne

Notes: Visit in August of 1992 by P.Hinz and R.M Landry (OGS OFR 5889)

Date: Aug 30, 2012

Geologist: Mark Puumala

Notes: Historic development on the Chrome Lake Mine site (MNDM Mineral Deposit Inventory record MDI52H14NW00002) resulted in the deposition of 2 mine development rock piles, one of which afforded helicopter access to the property, which is otherwise completely overgrown. Numerous collapsed buildings are still present on the site along with rail cars, rails, other historic mining equipment and miscellaneous debris. Two outcrops located in close proximity to the southern waste rock pile were briefly examined. To the south of the rock pile, sheared metasedimentary rocks are exposed (UTM Zone 16, 321431E 5538249N). Foliation in these rocks is oriented 070/55. An outcrop of serpentinized and hematitized ultramafic rock is exposed approximately 50 m west of the southern waste rock pile (UTM Zone 16, 321382E 5538265N). The rocks at this location are generally grey-green, with patchy red colouration where hematite alteration has occurred. The outcrop is crosscut by a 2 to 3 cm wide pegmatite vein. Adjacent to this vein there is a concentration of specular hematite, which also occurs as disseminated grains in the ultramafic rock. No chromite mineralization was observed in this outcrop. The chromite ore that was extracted from the mine in the 1930s can be found in the on-site rock piles. The ore material consists of disseminated chromite and massive chromitite from a podiform deposit that was protected from the metamorphic event that resulted in the serpentinization of the Puddy Lake intrusion (Whittaker 1986).

Reserves or Resources Data
Zone	Year	Category	Tonnes	Reference	Comments	Commodities
Chrome Lake Mine - A Zone	1938	Unclassified	907185	Hinz & Landry, OFR5889, 1994, p. 41-42 referenced from Merritt (1938)	1,000,000 tons @ 7% Cr2O3	Chromium 7 %
Chrome Lake Mine - G Zone	1938	Unclassified	1360777	Hinz & Landry, OFR5889, 1994, p. 41-42 referenced from Merritt (1938)	1,500,000 tons @ 2.3% Cr2O3	Chromium 2.3 %
Chrome Lake Mine - E Zone	1938	Unclassified	22680	Hinz & Landry, OFR5889, 1994, p. 41	25,000 tons @ 12% Cr2O3 down to 300 feet remaining after production ended	Chromium 12 %

Production Data
Year	Tonnes	Commodities	Reference	Comment
1937	8000		Hinz & Landry, OFR5889, 1994, p.4 referenced from Merritt (1938).	"E" Zone, 1936-1937: 8000 tons in high-grade ore.

References

Map - Garden-Obonga lakes sheet, District of Thunder Bay, geological compilation series

Publication Number: P0326 Scale: 1:126,720 Date: 1997

Author: Pye E.G., Baillie J.

Publisher Name: Ontario Dept. of Mines

Location:

Map - Obonga Lake area, west part, District of Thunder Bay

Publication Number: P0416 Scale: 1:15,840 Date: 1997

Author: Kustra C.R.

Publisher Name: Ontario Dept. of Mines

Location:

Book - OBONGA LAKE CHROMITE AREA, DIST. OF T.BAY., ODV VOL39, PT.2, P.51-60

Publication Number: ODM VOL.39 Date: 1930

Author: Graham, A.R.

Publisher Name:

Location: Thunder Bay RGP

Map - Obonga Lake area, east part

Publication Number: P0417 Scale: 1:15,840 Date: 1997

Author: Kustra C.R.

Publisher Name: Ontario Dept. of Mines

Location:

Book - CHROMITE DEPOSITS OF THE OBONGA LAKE AREA, DIST. OF T.B., PT.4, P.111-119

Publication Number: ODM V.40 Date: 1931

Author: Hurst, M.E.

Publisher Name:

Location: Thunder Bay RGP

Map - Geological series, Operation Ignace-Armstrong, Obonga Lake-Lac des Iles sheet, District of Thunder Bay

Publication Number: P0963 Scale: 1:126,720 Date: 1974

Author: Sage R.P., Breaks F.W., Stott G.M., McWilliams G.H., Robertson D.S.

Publisher Name: Ontario Division of Mines

Location:

File - Industrial Minerals Geologist's Files, Thunder Bay

Publication Number: Date:

Author:

Publisher Name:

Location: Thunder Bay RGP

File - Thunder Bay Resident Geologist Mineral Deposit Files

Publication Number: Min Dep Date:

Author:

Publisher Name:

Location: Thunder Bay RGP

Mono - Industrial Mineral Occurrences and Deposits in Northwest Ontario

Publication Number: OFR5889 Page: 38-43 Date: 1994

Author: Hinz P., Landry R.M.