Rio Tinto JORC Table 1 release

Rio Tinto PLC

21 February 2024

 

Notice to ASX/LSE                                                                                                                       

Mineral Resources and Ore Reserves updates

21 February 2024

Rio Tinto has today announced to the Australian Securities Exchange (ASX) changes in Mineral Resources and Ore Reserves to support its 2023 annual reporting[1], including: 

·      Decreased Mineral Resources at the Rio Tinto Kennecott (RTK) Bingham Canyon open pit deposit in Utah, United States of America.

·      Increased Ore Reserves and associated decreased Mineral Resources at the Rio Tinto Aluminium (RTA) Pacific Operations Amrun deposit in Queensland, Australia.

·      Revised classification for the Ore Reserves at the Iron Ore Company of Canada (IOC) operations in Newfoundland and Labrador, Canada.

Supporting information relating to the changes of Mineral Resources and Ore Reserves is set out in the Table 1 Release and its appendices. This release provides a summary of those changes.  Mineral Resources and Ore Reserves are quoted in this release on a 100 percent basis. Mineral Resources are reported in addition to Ore Reserves. The figures used to calculate Mineral Resources and Ore Reserves are often more precise than the rounded numbers shown in the tables, hence small differences may result if the calculations are repeated using the tabulated figures.   

These changes will be included in Rio Tinto's 2023 Annual Report, to be released to the market on 21 February 2024, which will set out in full Rio Tinto's Mineral Resources and Ore Reserves position as at 31 December 2023, and Rio Tinto's interests.  

Rio Tinto Kennecott 

Mineral Resources and Ore Reserves for the RTK Bingham Canyon open pit are presented in Table A and Table B[2]. Mineral Resources tonnes have decreased by 21 Mt (22%) as a result of the conversion of the East Wall Extension to Ore Reserves and removal of an opportunity to steepen the South Wall due to geotechnical concerns and changes to economic assumptions. There is an associated increase in Ore Reserves as a result of the East Wall conversion, which has been offset by depletion.

Rio Tinto Aluminium Pacific Operations - Amrun

Mineral Resources and Ore Reserves for the RTA Amrun deposit are presented in Table C and Table D[3]. Mineral Resources exclusive of Ore Reserves have decreased by 55 Mt (7%) at Amrun due to conversion of Mineral Resources to Ore Reserves resulting from a routine review of price assumptions over the life of the mine, and updated orebody knowledge.

Ore Reserves have increased by 149 Mt (19%) at Amrun. The increase in Ore Reserves is associated with a routine review of price assumptions over the life of the mine, and updated orebody knowledge.  There has been no material change to other modifying factors, including governmental, tenure, environmental, cultural heritage, community or operational.

Iron Ore Company of Canada

Mineral Resources and Ore Reserves for IOC are presented in Table E and Table F[4]. The classification of the Ore Reserves has changed as a result of reclassification of a significant proportion of the Proved Ore Reserves to Probable Ore Reserves. The change reflects a lower level of confidence in the modifying factors in areas supported by older data which does not have recovery and grind energy geometallurgical data.

Table A            Rio Tinto Kennecott Copper Bingham Canyon open pit Mineral Resources as at 31 December 2023 

Likely mining method(1)

Measured Mineral Resources

Indicated Mineral Resources

Total Measured and Indicated Mineral

as at 31 December 2023

as at 31 December 2023

Resources as at 31 December 2023

Tonnage

Grade

Tonnage

Grade

Tonnage

Grade

Copper(2)

Mt

% Cu

g/t Au

g/t Ag

% Mo

Mt

% Cu

g/t Au

g/t Ag

% Mo

Mt

% Cu

g/t Au

g/t Ag

% Mo

Bingham Canyon (US)

- Bingham Open Pit(3)

O/P

38

0.47

0.15

2.47

0.020

22

0.39

0.16

2.66

0.016

59

0.44

0.15

2.54

0.018

Inferred Mineral Resources

Total Mineral Resources

Rio Tinto interest

Total Mineral Resources

as at 31 December 2023

as at 31 December 2023

as at 31 December 2022

Tonnage

Grade

Tonnage

Grade

Tonnage

Grade

Copper(2)

Mt

% Cu

g/t Au

g/t Ag

% Mo

Mt

% Cu

g/t Au

g/t Ag

% Mo

%

Mt

% Cu

g/t Au

g/t Ag

% Mo

Bingham Canyon (US)

- Bingham Open Pit(3)

12

0.26

0.20

2.56

0.005

72

0.41

0.16

2.55

0.016

100.0

93

0.43

0.15

2.24

0.016

1.   Likely mining method: O/P = open pit/surface. 

2.   Copper Mineral Resources are reported on a dry in situ weight basis. 

3.   Bingham Canyon Open Pit Mineral Resources molybdenum grades interpolated from exploration drilling assays have been factored based on a long reconciliation history to blast hole and mill samples. 

Table B            Rio Tinto Kennecott Copper Bingham Canyon open pit Ore Reserves as at 31 December 2023 

Type of mine(1)

Proved Ore Reserves

Probable Ore Reserves

Total Ore Reserves

as at 31 December 2023

as at 31 December 2023

as at 31 December 2023

Tonnage

Grade

Tonnage

Grade

Tonnage

Grade

Copper(2)

Mt

% Cu

g/t Au

g/t Ag

% Mo

Mt

% Cu

g/t Au

g/t Ag

% Mo

Mt

% Cu

g/t Au

g/t Ag

% Mo

Bingham Canyon (US)

- Bingham Open Pit(3)

O/P

470

0.37

0.18

1.98

0.038

360

0.36

0.18

1.98

0.028

829

0.37

0.18

1.98

0.033

Average mill recovery %

Rio Tinto interest

Rio Tinto share

Total Ore Reserves

recoverable metal

as at 31 December 2022

Tonnage

Grade

Copper(2)

Cu

Au

Ag

Mo

%

Mt Cu

Moz Au

Moz Ag

Mt Mo

Mt

% Cu

g/t Au

g/t Ag

% Mo

Bingham Canyon (US)

- Bingham Open Pit(3)

89

69

71

63

100.0

2.681

3.257

37.686

0.176

880

0.38

0.18

1.97

0.033

1.    Type of Mine: O/P = open pit/surface. 

2.   Copper Ore Reserves are reported as dry mill feed tonnes. 

3.   Bingham Canyon Open Pit Ore Reserves molybdenum grades interpolated from exploration drilling assays have been factored based on a long reconciliation history to blast hole and mill samples. 

Table C            Rio Tinto Aluminium Pacific Operations Mineral Resources as at 31 December 2023 

	Likely mining method(1)	Measured Mineral Resources			Indicated Mineral Resources			Total Measured and Indicated Mineral
		as at 31 December 2023			as at 31 December 2023			Resources as at 31 December 2023
		Tonnage	Grade		Tonnage	Grade		Tonnage	Grade
Bauxite		Mt	% Al2O3	% SiO2	Mt	% Al2O3	% SiO2	Mt	% Al2O3	% SiO2
Rio Tinto Aluminium (Australia)(2)
- Amrun	O/P	115	49.2	11.7	388	49.7	11.7	504	49.6	11.7
- East Weipa and Andoom	O/P	43	49.9	8.8	-	-	-	43	49.9	8.8
- Gove	O/P	9	48.1	8.9	0.4	47.8	8.9	9	48.1	8.9
- North of Weipa	O/P	-	-	-	202	52.0	11.1	202	52.0	11.1
Total (Australia)		167	49.3	10.8	591	50.5	11.5	759	50.2	11.4

	Inferred Mineral Resources			Total Mineral Resources			Rio Tinto interest	Total Mineral Resources
	as at 31 December 2023			as at 31 December 2023				as at 31 December 2022
	Tonnage	Grade		Tonnage	Grade			Tonnage	Grade
Bauxite	Mt	% Al2O3	% SiO2	Mt	% Al2O3	% SiO2	%	Mt	% Al2O3	% SiO2
Rio Tinto Aluminium (Australia)(2)
- Amrun	285	51.7	12.1	788	50.4	11.9	100.0	843	50.6	11.8
- East Weipa and Andoom	-	-	-	43	49.9	8.8	100.0	53	49.3	8.5
- Gove	0.01	46.9	8.1	9	48.1	8.9	100.0	13	48.3	9.0
- North of Weipa	1,248	51.8	11.4	1,451	51.9	11.4	100.0	1,330	52.0	11.6
Total (Australia)	1,533	51.8	11.5	2,291	51.3	11.5		2,240	51.4	11.6

1.   Likely mining method: O/P = open pit/surface.

2.   Rio Tinto Aluminium bauxite Mineral Resources are stated as dry product tonnes and total alumina and silica grades.

Table D            Rio Tinto Aluminium Pacific Operations Ore Reserves as at 31 December 2023 

	Type of mine(1)	Proved Ore Reserves			Probable Ore Reserves			Total Ore Reserves
		as at 31 December 2023			as at 31 December 2023			as at 31 December 2023
		Tonnage	Grade		Tonnage	Grade		Tonnage	Grade
Bauxite(2)		Mt	% Al2O3	% SiO2	Mt	% Al2O3	% SiO2	Mt	% Al2O3	% SiO2
Rio Tinto Aluminium (Australia)(3)
- Amrun	O/P	263	53.9	9.2	688	54.5	9.0	950	54.3	9.1
- East Weipa and Andoom	O/P	69	50.5	7.9	3	49.5	8.7	72	50.5	8.0
- Gove	O/P	57	50.2	6.4	0.7	50.5	5.0	58	50.2	6.4
Total (Australia)		388	52.8	8.6	692	54.4	9.0	1,080	53.8	8.8

	Rio Tinto interest	Rio Tinto share recoverable mineral		Total Ore Reserves as at 31 December 2022
				Tonnage	Grade
Bauxite(2)	%	Mt		Mt	% Al2O3	% SiO2
Rio Tinto Aluminium (Australia)(3)
- Amrun	100.0	950		801	54.6	8.9
- East Weipa and Andoom	100.0	72		59	51.7	7.1
- Gove	100.0	58		56	50.5	5.8
Total (Australia)	100.0	1,080		916	54.2	8.6

1.     Type of Mine: O/P = open pit/surface. 

2.     Bauxite Ore Reserves are stated as recoverable Ore Reserves of marketable product after accounting for all mining and processing losses. Mill recoveries are therefore not shown.

3.     Australian bauxite Ore Reserves are stated as dry tonnes and total alumina and silica grade.

Table E                        Iron Ore Company of Canada Mineral Resources as at 31 December 2023 

Likely mining method(1)

Measured Mineral Resources

Indicated Mineral Resources

Total Measured and Indicated Mineral

as at 31 December 2023

as at 31 December 2023

Resources as at 31 December 2023

Tonnage

Grade

Tonnage

Grade

Tonnage

Grade

Iron ore(2)

Mt

% Fe

% SiO2

% Al2O3

% P

Mt

% Fe

% SiO2

% Al2O3

% P

Mt

% Fe

% SiO2

% Al2O3

% P

Iron Ore Company of Canada (Canada)(3)

O/P

171

40.8

35.8

0.2

0.02

720

38.5

37.1

0.2

0.03

891

38.9

36.9

0.2

0.03

Inferred Mineral Resources

Total Mineral Resources

Rio Tinto interest

Total Mineral Resources

as at 31 December 2023

as at 31 December 2023

as at 31 December 2022

Tonnage

Grade

Tonnage

Grade

Tonnage

Grade

Iron ore(2)

Mt

% Fe

% SiO2

% Al2O3

% P

Mt

% Fe

% SiO2

% Al2O3

% P

%

Mt

% Fe

% SiO2

% Al2O3

% P

Iron Ore Company of Canada (Canada)(3)

751

38.2

35.7

0.2

0.03

1,641

38.6

36.3

0.2

0.03

58.7

1,666

38.7

37.4

0.2

0.03

1.     Likely mining method: O/P = open pit/surface. 

2.     Iron ore Mineral Resources are stated on a dry in situ weight basis.

3.     The reported Mineral Resources have the potential to produce marketable product (57% pellets and 43% concentrate for sale at a natural moisture content of 2%) comprising 73 million tonnes at 65% iron 2.7% silica (Measured), 301 million tonnes at 65% iron 2.7% silica (Indicated) and 308 million tonnes at 65% iron 2.7% silica (Inferred) using process recovery factors derived from current IOC concentrating and pellet operations. LOI is not determined for resource drilling samples, so no estimate of % LOI is available for Mineral Resources.

Table F             Iron Ore Company of Canada Ore Reserves as at 31 December 2023 

	Type of mine(1)	Proved Ore reserves			Probable Ore Reserves			Total Ore Reserves
		as at 31 December 2023			as at 31 December 2023			as at 31 December 2023
		Tonnage	Grade		Tonnage	Grade		Tonnage	Grade
Iron ore(2)		Mt	% Fe	% SiO2	Mt	% Fe	% SiO2	Mt	% Fe	% SiO2
Iron Ore Company of Canada (Canada)(3)	O/P	149	65.0	2.8	275	65.0	2.8	423	65.0	2.8

	Rio Tinto interest	Rio Tinto share		Total Ore Reserves
		marketable product		as at 31 December 2022
				Tonnage	Grade
Iron ore(2)	%	Mt		Mt	% Fe	% SiO2
Iron Ore Company of Canada (Canada)(3)	58.7	249		453	65.0	3.0

1.   Type of Mine: O/P = open pit/surface. 

2.   Ore Reserves of iron ore are shown as recoverable Ore Reserves of marketable product after accounting for all mining and processing losses. Mill recoveries are therefore not shown.

3.   Iron Ore Company of Canada Ore Reserves are reported as marketable product (57% pellets and 43% concentrate for sale) at a natural moisture content of 2%. The marketable product is derived from mined material comprising 357 million dry tonnes at 38% iron, 36% silica, 0.23% alumina, 0.022% phosphorus (Proved) and 651 million dry tonnes at 38% iron, 35% silica, 0.19% alumina, 0.023% phosphorus (Probable) using process recovery factors derived from current IOC concentrating and pellet operations. No meaningful relationship has been established between the product and feed grades of alumina and phosphorus, so these grades cannot be reported for Ore Reserves. Saleable product is produced to meet silica grade specifications, so the Ore Reserves silica grade is the targeted silica grade for the currently anticipated long-term product mix. Loss on Ignition (LOI) is not determined for resource drilling samples, so no estimate of % LOI is available for Ore Reserves.

Contacts

Please direct all enquiries to [e-mail]

Media Relations, United Kingdom Matthew Klar M [phone] David Outhwaite M [phone]	Media Relations, Australia Matt Chambers M [phone] Jesse Riseborough M [phone] Alyesha Anderson  M [phone]  Michelle Lee  M [phone]	Media Relations, Americas Simon Letendre M [phone] Malika Cherry M [phone] Vanessa Damha   M [phone]
Investor Relations, United Kingdom Menno Sanderse M [phone] David Ovington M [phone] Laura Brooks    M [phone]	Investor Relations, Australia Tom Gallop M [phone] Amar Jambaa M [phone]
Rio Tinto plc 6 St James's Square London SW1Y 4AD United Kingdom T [phone] Registered in England No. 719885	Rio Tinto Limited Level 43, 120 Collins Street Melbourne 3000 Australia T [phone] Registered in Australia ABN 96 004 458 404

This announcement is authorised for release to the market by Andy Hodges, Rio Tinto's Group Company Secretary

riotinto.com

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[1] These Mineral Resources and Ore Reserves were reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves, 2012 (JORC Code) and the ASX Listing Rules in a release to the ASX dated 21 February 2024 titled "Ore Reserve and Mineral Resource updates: supporting information and Table 1 checklists" (Table 1 Release). Rio Tinto confirms that it is not aware of any new information or data that materially affects the information included in the Table 1 Release, that all material assumptions and technical parameters underpinning the estimates in the Table 1 Release continue to apply and have not materially changed, and that the form and context in which the Competent Persons' findings are presented have not been materially modified.

[2] The Competent Persons responsible for the information in the Table 1 Release that relates to Rio Tinto Kennecott Mineral Resources were Pancho Rodriguez and Ana Chiquini, who are Members of the Australasian Institute of Mining and Metallurgy (MAusIMM). The Competent Person responsible for the information in the Table 1 Release that relates to Rio Tinto Kennecott Ore Reserves is Brady Pett (MAusIMM).

[3] The Competent Person responsible for the information in the Table 1 Release that relates to Rio Tinto Aluminium Pacific Operations Mineral Resources is Angus Mc Intyre (MAusIMM). The Competent Person responsible for the information in the Table 1 Release that relates to Rio Tinto Aluminium Pacific Operations Ore Reserves is William Saba (MAusIMM).

[4] The Competent Persons responsible for the information in the Table 1 Release that relates to Iron Ore Company of Canada Mineral Resources were Ramsey Way, Mervin McDonald and Beverly Power, who are Members of Professional Engineers and Geoscientists of Newfoundland and Labrador. The Competent Persons responsible for the information in the Table 1 Release that relates to Iron Ore Company of Canada Ore Reserves were Rodney Williams and Stéphane Roche, who are Members of Professional Engineers and Geoscientists of Newfoundland and Labrador.

 

END