2003 Reserve Assessing the Bauxite Resources.



 EXHIBIT 4.2 
  
 [Letterhead of the Non-Ferrous Metal Mineral Geological Survey Center*] 
  
 2003 REPORT ASSESSING THE BAUXITE RESOURCES/RESERVES OF 
 ALUMINUM CORPORATION OF CHINA LIMITED** 
  
 In order to disclose to the public the available bauxite reserves and non-reserve bauxite resources of its mines and its jointly operated mines as at December 31, 2003,
Chalco, in February 2004, engaged the Non-Ferrous Metal Mineral Geological Survey Center* (the “Survey Center”) to carry out an assessment of its bauxite resources/reserves in 2003 and submit the 2003 Report Assessing the Bauxite Resources
of Aluminum Corporation of China Limited. The data and perspectives presented in the report were based on information provided by Chalco and the relevant mines. The information has been examined and deemed reliable by the Survey Center. 

 
 The bauxite required by Chalco’s alumina refineries comes from three sources: mines
owned by Chalco, jointly operated mines and other ore providers. This report only assesses the resources of the 8 mines owned by Chalco, totaling 43 stopes (mining areas/sections), and 14 jointly operated mines. When compared to the scope of the
assessment carried out by SRK in 2001 and the Survey Center in 2002, this assessment adds the Xiangwang and Chaichang stopes of the Shanxi branch’s Xiaoyi mine and the Baiquan stope of the Shandong branch’s Yangquan mine among the mines
owned by Chalco and the five jointly operated mines, namely Shangtan, Yangpo, Shaping, Jindui and Shicao, added by the Shanxi branch. A total of three stopes in self-owned mines and five jointly operated mines have been added. The remaining mines
(stopes) are consistent with the scope of the assessment carried out by SRK in 2001. Accordingly, the subject of this assessment remains the eight self-owned mines and nine jointly operated mines assessed by SRK in 2001. Additionally, three new
stopes in self-owned mines and five new jointly operated mines were assessed. 
  
 The eight new mining areas are located in Shanxi Province. They are stable sedimentary hydraulic bauxite deposits which are free of major disturbances. The reserves were estimated based on the extent of the continuous ore bodies as
delimited by marginal grade, industrial grade, admissible thickness and admissible maximal thickness of interlayer. The extent of the ore bodies was determined by the exploration samples which attained industrial grade and the polygon formed by
linking the actual sampling locations. The ore grade was calculated by using the sample length weighting method. The Survey Center deemed the number of samples taken sufficient for this type of mineral deposit. 
  
 According to SRK’s mineral deposit grouping, these eight new mining areas fall into
group three, namely thin-bed mineral deposits. The ore bodies are not characterized by any abrupt change in thickness or quality. The reserve classification determined in accordance with the changes in the thickness and quality of the ore bodies and
the exploration net is shown in Table 1. 
  
 Table 1. Sample Net
Used To Estimate Bauxite Reserves 
  

							
	 Name of mineral deposit

	  	 Mineral deposit grouping

	  	 Sample net

	  	 Reserve classification


	 Xiangwang, Chaichang, Shangtan
	  	 Group 3 - stable
 sedimentary
mineral
 deposit without any
 major disturbances
	  	50 x 50 m	  	 proven (grade controlled,
 A grade)

	 Yangpo, Shaping, Jindui
	  	  	100 x 100 m or 70 x 70 m	  	proven (B grade)
	 Shicao, Baiquan
	  	  	140 x 140 m or 200 x 200 m	  	probable (C grade)








 The methods and principles used in the current resource assessment are completely consistent with those of SRK and comply
with the relevant provisions of the US Securities and Exchange Commission’s Industry Guide 7. Specifically, the assessment is based on the basic database of the 2002 Report Assessing the Bauxite Resources of Chalco and the data sources are the
information on bauxite reserves, adjusted production plans, extraction loss rate, depletion rate, ore body floor and adjacent formation grade as at December 31, 2003 provided by the head office and branches of Chalco and mining output in 2003. The
new data as at December 31, 2003 was substituted for the old data (as at December 31, 2002) in the basic database of the 2002 Report Assessing the Bauxite Resources of Chalco, then analyzed, induced and collated to produce the bauxite reserves and
non-reserve bauxite resources held by Chalco as at December 31, 2003 and bauxite consumption in 2003. 
  
 Based on the data provided by Chalco and after considering extraction loss and depletion, the proven and probable bauxite resources which have been incorporated into approved mine production plans and which fall
within the current scope of the mining permits were estimated and converted into reserves. All proven and probable resources which have not yet been included in the production plans are listed separately as non-reserve bauxite resources. Tables 2(a)
and (b) show the bauxite reserves and non-reserve bauxite resources contained in Chalco’s mines as at December 31, 2003. Tables 3(a) and (b) show the data on the resources of the 14 jointly operated mines. One hundred percent of the ore
produced by the jointly operated mines is sold to Chalco. The data in Tables 3(a) and (b) does not include the other 12 jointly operated mines not assessed by the Survey Center. 
  
 As at December 31, 2003, Chalco’s mines had bauxite reserves of 181.7 million tonnes and the jointly operated mines had bauxite
reserves of 25.3 million tonnes. In addition to the aforementioned reserves, Chalco’s mines had 82.4 million tonnes of non-reserve bauxite resources and the jointly operated mines had 21.7 million tonnes of non-reserve bauxite resources. The
aforementioned proven and probable reserves fully comply with the US Securities and Exchange Commission’s Industry Guide 7. When making a decision, investors should mainly consider these reserves. 
  
 Tables 4(a) and (b) and Tables 5(a) and (b) respectively show the consumption of bauxite
reserves and non-reserve bauxite resources in Chalco’s mines and the jointly operated mines in 2003. Chalco’s mine reserves increased by 27.3 million tonnes and non-reserve resources decreased by 12.3 million tonnes, translating into a
total reserve and resource increase of 15 million tonnes in self-owned mines; jointly operated mine reserves increased by 0.2 million tonnes and non-reserve resources increased by 2.7 million tonnes, translating into a total reserve and resource
increase of 2.9 million tonnes in jointly operated mines. This indicates that Chalco’s progress in acquiring bauxite resources in 2003 was good. 
  
 The negative number for consumption indicates that, this year as compared to last year, reserves/non-reserve resources did not decrease but increased. The main reasons
for this are adjustments to production plans, the new stopes and jointly operate mines and the exploration upgrades that increased reserves or non-reserve resources this year. 
  

 2 








 The main reasons for the decrease in reserves in this assessment are extraction and exploration related decreases. New
delimitation of ore bodies also resulted in a reduction in some reserves. The main reason for the increase in reserves was the adjustments to production plans which caused the conversion of non-reserve resources into reserves, resulting in a
decrease in non-reserve resources. Additionally, changes in extraction loss rate and depletion rate also caused small increases or decreases in reserves. The main reason for the increase in non-reserve resources was the three new self-owned mine
stopes and the five new jointly operated mines. 
  

			
	 (Signed) Yang Bing
	 	 March 25, 2004


  

			
	 Yang Bing:
	  	senior resource geologist, state-registered mineral reserve assessor and vice-chairman of the Non-Ferrous Metal Mineral Geological Survey Center.

  

	*	Translator’s Note: 

  
 The name of this entity has been translated by us and may not be its actual English name, if any. 
  

	**	This document is an English translation of the original Chinese document 

  
 Table 2 (a) 
  
 Estimate of Bauxite Reserves at Chalco Mines 
  

													
	 	  	As at December 31, 2003


	 Arranged by Enterprise, Mine and Stope

	  	Estimate of Available Bauxite Reserves


	 Enterprise

	  	 Mine

	  	 Stope

	  	Qty.

	  	Al2O3

	  	SiO2

	  	Al/Si
Ratio


	 	  	 	  	 	  	Million tonnes	  	%	  	%	  	A:S
	 Pingguo
	  	 Pingguo
	  	 Natang, Gu’an, Bulu, Neiyin, Burong, Nadou, Naduan
	  	49.0	  	60.5	  	5.6	  	10.8
	 	  	 	  	 Taiping(1)
	  	45.6	  	54.3	  	3.5	  	15.5
	 Guizhou
	  	 Mine #1
	  	 Xiaoshanba
	  	9.7	  	66.8	  	12.1	  	5.5
	 	  	 Mine #2
	  	 Changchong River, Yanlong, Lindai
	  	12.8	  	68.1	  	9.5	  	7.2
	 Shanxi
	  	 Xiaoyi
	  	 Ke’e, Xihedi
	  	21.6	  	63.7	  	13.5	  	4.7
	 Zhengzhou
	  	 Mianchi
	  	 Guangou
	  	7.1	  	67.2	  	9.6	  	7.0
	 	  	 Luoyang
	  	 Zhangyaoyuan, Jiagou
	  	15.0	  	61.6	  	9.4	  	6.5
	 	  	 Xiaoguan
	  	 Chadian, Zhulingou
	  	17.1	  	64.4	  	15.6	  	4.1
	 Shandong
	  	 Yangquan
	  	 Baijiazhuang, Shantounan
	  	3.8	  	60.1	  	12.4	  	4.8
	 	  	 	  	 	  	
	  	
	  	
	  	

	 Total (Avg)
	  	 	  	 	  	181.7	  	60.9	  	8.2	  	7.4
	 	  	 	  	 	  	
	  	
	  	
	  	

	 Arranged according to reserve grade
	  	 	  	 	  	 	  	 	  	 	  	 
	 Proven reserves
	  	 	  	 	  	35.7	  	63.6	  	8.3	  	7.7
	 Probable reserves
	  	 	  	 	  	146.0	  	60.2	  	8.2	  	7.4
	 	  	 	  	 	  	
	  	
	  	
	  	

	 Total (Avg.) reserves
	  	 	  	 	  	181.7	  	60.9	  	8.2	  	7.4
	 	  	 	  	 	  	
	  	
	  	
	  	


  
 Table 2 (b)

 Estimate of Non-Reserve Bauxite Resources at Chalco Mines 
  

													
	 	  	 	  	 	  	As at December 31, 2003


	 Arranged by Enterprise, Mine and Stope

	  	Available Non-Reserve Bauxite
Resources


	 Enterprise

	  	 Mine

	  	 Stope

	  	Qty.

	  	Al2O3

	  	SiO2

	  	Al/Si
Ratio


	 	  	 	  	 	  	Million tonnes	  	%	  	%	  	A:S
	 Pingguo
	  	 Pingguo
	  	 Yalang
	  	14.1	  	48.9	  	10.2	  	4.8
	 	  	 	  	 North Taiping, South Taiping(1)
	  	6.1	  	50.6	  	4.0	  	12.6
	 Guizhou
	  	 Mine #2
	  	 Changchong River, Yanlong, Lindai
	  	2.4	  	66.5	  	11.3	  	5.9
	 Shanxi
	  	 Xiaoyi
	  	 Ke’e, Xihedi, Xiangwang,(2) Chaichang(2)
	  	25.5	  	67.6	  	10.6	  	6.4
	 Zhengzhou
	  	 Xiaoguan
	  	 Hongtupo
	  	31.0	  	65.2	  	13.9	  	4.7
	 Shandong
	  	 Yangquan
	  	 Baiquan(2)
	  	3.2	  	64.1	  	11.3	  	5.7
	 	  	 	  	 	  	
	  	
	  	
	  	

	 Total (Avg)
	  	 	  	 	  	82.4	  	62.1	  	11.3	  	5.5
	 	  	 	  	 	  	
	  	
	  	
	  	




	(1)	Extraction has not yet commenced at Taiping stope. This report presents data on resources, reserves and production plans. At present no production data or information on transport
arrangements are available. 


	(2)	Xiangwang, Chaichang and Baiquan in Table 2(b) are new stopes added by Chalco in 2003. 

  

 3 








 Table 3 (a) 
 Estimate of Bauxite Reserves at Chalco’s Jointly Operated Mines(1)

  

											
	 	  	 	  	As at December 31, 2003


	 Arranged by Enterprise and Mine

	  	Estimate of Available Bauxite Reserves


	 Enterprise

	  	 Jointly Operated Mine

	  	Qty.

	  	Al2O3

	  	SiO2

	  	Al/Si
Ratio


	 	  	 	  	Million tonnes	  	%	  	%	  	A:S
	 Guizhou
	  	 Goujiang
	  	1.2	  	64.4	  	10.1	  	6.4
	 Shanxi
	  	 Wenquanxiang
	  	6.2	  	60.3	  	10.0	  	6.0
	 Zhengzhou
	  	 Zhanggou Hongda
	  	0.2	  	69.1	  	7.6	  	9.1
	 	  	 Shecun
	  	2.1	  	64.2	  	13.4	  	4.8
	 	  	 Jiagou(2)
	  	1.2	  	65.9	  	10.7	  	6.2
	 	  	 Zhishe
	  	0.0	  	68.6	  	9.7	  	7.1
	 	  	 Dujiagou
	  	3.3	  	69.2	  	8.5	  	8.1
	 	  	 Xiangcaowa
	  	1.1	  	69.4	  	6.8	  	10.2
	 	  	 Jiajiawa
	  	10.0	  	70.5	  	7.4	  	9.5
	 	  	 	  	
	  	
	  	
	  	

	 Total (Avg)
	  	 	  	25.3	  	66.7	  	9.0	  	7.4
	 	  	 	  	
	  	
	  	
	  	

	 Arranged according to reserve grade
	  	 	  	 	  	 	  	 	  	 
	 Proven reserves
	  	 	  	13.4	  	69.4	  	8.1	  	8.6
	 Probable reserves
	  	 	  	11.9	  	63.7	  	9.9	  	6.4
	 	  	 	  	
	  	
	  	
	  	

	 Total (Avg.) reserves
	  	 	  	25.3	  	66.7	  	9.0	  	7.4
	 	  	 	  	
	  	
	  	
	  	


  
 Table 3 (b)

  
 Estimate of Non-Reserve Bauxite Resources at Chalco
Jointly Operated Mines(1) 
  

											
	 	  	 	  	As at December 31, 2003


	 Arranged by Enterprise and Mine

	  	Available Non-Reserve Bauxite
Resources


	 Enterprise

	  	 Jointly Operated Mine

	  	Qty.

	  	Al2O3

	  	SiO2

	  	Al/Si
Ratio


	 	  	 	  	Million tonnes	  	%	  	%	  	A:S
	 Guizhou
	  	 Goujiang
	  	2.6	  	66.9	  	7.7	  	8.7
	 Shanxi
	  	 Wenquanxiang
	  	0.0	  	0.0	  	0.0	  	0.0
	 	  	 Shangtan(3)
	  	0.6	  	71.1	  	7.4	  	9.6
	 	  	 Yangpo(3)
	  	2.1	  	64.0	  	9.0	  	7.1
	 	  	 Shaping(3)
	  	1.8	  	69.8	  	9.3	  	7.5
	 	  	 Jindui(3)
	  	1.6	  	62.9	  	11.5	  	5.5
	 	  	 Shicao(3)
	  	1.4	  	69.4	  	9.2	  	7.5
	 Zhengzhou
	  	 Shecun
	  	5.9	  	65.2	  	13.0	  	5.0
	 	  	 Dujiagou
	  	2.6	  	69.5	  	8.3	  	8.4
	 	  	 Xiangcaowa
	  	0.9	  	72.5	  	4.1	  	17.9
	 	  	 Jiajiawa
	  	2.1	  	72.8	  	6.0	  	12.1
	 	  	 	  	
	  	
	  	
	  	

	 Total (Avg)
	  	 	  	21.7	  	67.5	  	9.5	  	7.1
	 	  	 	  	
	  	
	  	
	  	




	(1)	Tables 3(a) and (b) do not include the other 12 jointly operated mines not assessed by the Investigation Center. 


	(2)	Note the difference between Jiagou (Chinese characters) and Jiagou (Chinese characters). Jiagou (Chinese characters) is a stope owned by the Luoyang mine whereas Jiagou (Chinese
characters) is a jointly operated mine. The pinyin transliteration of both is the same, thus making them easy to confuse. 


	(3)	Shangtan, Yangpo, Shaping, Jindui and Shicao in Table 3(b) are new jointly operated mines added by Chalco in 2003. 

  

 4 








 Table 4 (a) 
  
 Decrease in Bauxite Reserves at Chalco Mines(1) 
  

											
	 Arranged by Enterprise, Mine and Stope

	  	Qty. Available at
Yearend

	  	Qty. Available at
Yearend

	  	Decrease in
Reserves in


	 Enterprise

	  	 Mine

	  	 Stope

	  	2002 (Million
tonnes)

	  	2003 (Million
tonnes)

	  	2003 (Million
tonnes)


	 Pingguo
	  	 Pingguo
	  	 Natang, Gu’an, Bulu, Neiyin, Burong, Nadou, Naduan(2)
	  	44.8	  	49.0	  	-4.2
	 	  	 	  	 South Taiping, North Taiping(3)
	  	19.4	  	45.6	  	-26.2
	 Guizhou
	  	 Mine #1
	  	 Xiaoshanba
	  	9.8	  	9.7	  	0.0
	 	  	 Mine #2
	  	 Changchong River, Yanlong, Lindai
	  	13.7	  	12.8	  	0.9
	 Shanxi
	  	 Xiaoyi
	  	 Ke’e, Xihedi
	  	22.3	  	21.6	  	0.7
	 Zhengzhou
	  	 Mianchi
	  	 Guangou
	  	6.8	  	7.1	  	-0.3
	 	  	 Luoyang
	  	 Zhangyaoyuan, Jiagou
	  	16.8	  	15.0	  	1.8
	 	  	 Xiaoguan
	  	 Chadian, Zhulingou
	  	17.1	  	17.1	  	0.0
	 Shandong
	  	 Yangquan
	  	 Baijiazhuang, Shantounan
	  	3.8	  	3.8	  	0.0
	 	  	 	  	 	  	
	  	
	  	

	 Total
	  	 	  	 	  	154.4	  	181.7	  	-27.3
	 	  	 	  	 	  	
	  	
	  	

	 Arranged according to reserve grade
	  	 	  	 	  	 	  	 	  	 
	 Proven reserves
	  	 	  	 	  	30.7	  	35.7	  	-5.0
	 Probable reserves
	  	 	  	 	  	123.7	  	146.0	  	-22.3
	 	  	 	  	 	  	
	  	
	  	

	 Total
	  	 	  	 	  	154.4	  	181.7	  	-27.3
	 	  	 	  	 	  	
	  	
	  	


  
 Table 4 (b)

 Decrease in Non-Reserve Bauxite Resources at Chalco Mines(1) 
  

											
	 Arranged by Enterprise, Mine and Stope

	  	Qty. Available at
Yearend

	  	Qty. Available at
Yearend

	  	Decrease in
Non-Reserve
Resources


	 Enterprise

	  	Mine

	 	 Stope

	  	2002 (Million
tonnes)

	  	2003 (Million
tonnes)

	  	in 2003 (Million
tonnes)


	 Pingguo
	  	Pingguo	 	 Jiangzhou, Yalang, Naduan(4)
	  	20.4	  	14.1	  	6.3
	 	  	 	 	 North Taiping, South Taiping
	  	32.6	  	6.1	  	26.4
	 Guizhou
	  	Mine #2	 	 Changchong River,Yanlong, Lindai
	  	2.7	  	2.4	  	0.3
	 Shanxi
	  	Xiaoyi	 	 Ke’e, Xihedi, Xiangwang,(5) Chaichang(5)
	  	8.0	  	25.5	  	-17.5
	 Zhengzhou
	  	Xiaoguan	 	 Hongtupo
	  	31.0	  	31.0	  	0.0
	 Shandong
	  	Yangquan	 	 Baiquan(5)
	  	 	  	3.2	  	-3.2
	 	  	 	 	 	  	
	  	
	  	

	 Total
	  	 	 	 	  	94.7	  	82.4	  	12.3
	 	  	 	 	 	  	
	  	
	  	


  

	(1)	Negative figures in the tables indicate that reserves or non-reserve resources this year have increased over last year. 

  

	(2)	The Naduan stope is not included in the quantity available at the end of 2002. 

  

	(3)	The decrease at South Taiping and North Taiping: quantity available at South Taiping at the end of 2002 - quantity available at Taiping (South Taiping + North Taiping) at the end of
2003. 

  

	(4)	The figure for the end of 2002 is the amount available at Jiangzhou, Yalang and Naduan stopes, whereas the figure for the end of 2003 is the quantity available at the Jiangzhou and
Yalang stopes. 

  

	(5)	Xiangwang, Chaichang and Baiquan are new stopes added by Chalco in 2003. 

  

 5 








 Table 5 (a) 
  
 Decrease in Bauxite Reserves at Chalco Jointly Operated Mines(1) 
  

									
	 Arranged by Enterprise and Mine

	  	Qty. Available at
Yearend

	  	Qty. Available at
Yearend

	  	Decrease in
Reserves in


	 Enterprise

	  	 Jointly Operated Mine

	  	2002 (Million
tonnes)

	  	2003 (Million
tonnes)

	  	2003 (Million
tonnes)


	 Guizhou
	  	 Goujiang
	  	1.2	  	1.2	  	0.0
	 Shanxi
	  	 Wenquanxiang
	  	6.9	  	6.2	  	0.7
	 Zhengzhou
	  	 Zhanggou Hongda
	  	0.3	  	0.2	  	0.1
	 	  	 Shecun
	  	2.1	  	2.1	  	0.0
	 	  	 Jiagou(2)
	  	2.4	  	1.2	  	1.1
	 	  	 Zhishe
	  	0.1	  	0.0	  	0.1
	 	  	 Dujiagou
	  	3.3	  	3.3	  	0.0
	 	  	 Xiangcaowa
	  	0.5	  	1.1	  	-0.6
	 	  	 Jiajiawa
	  	8.4	  	10.0	  	-1.6
	 	  	 	  	
	  	
	  	

	 Total
	  	 	  	25.1	  	25.3	  	-0.2
	 	  	 	  	
	  	
	  	

	 Arranged according to reserve grade
	  	 	  	 	  	 	  	 
	 Proven reserves
	  	 	  	13.0	  	13.4	  	-0.4
	 Probable reserves
	  	 	  	12.1	  	11.9	  	0.2
	 	  	 	  	
	  	
	  	

	 Total
	  	 	  	25.1	  	25.3	  	-0.2
	 	  	 	  	
	  	
	  	


  
 Table 5 (b)

  
 Decrease in Non-Reserve Bauxite Reserves at Chalco
Jointly Operated Mines(1) 
  

									
	 Arranged by Enterprise and Mine

	  	Qty. Available at
Yearend

	  	Qty. Available at
Yearend

	  	Decrease in
Non-Reserve
Resources


	 Enterprise

	  	 Jointly Operated Mine

	  	2002 (Million
tonnes)

	  	2003 (Million
tonnes)

	  	in 2003 (Million
tonnes)


	 Guizhou
	  	 Goujiang
	  	2.8	  	2.6	  	0.2
	 Shanxi
	  	 Wenquanxiang
	  	2.1	  	0.0	  	2.1
	 	  	 Shangtan(3)
	  	 	  	0.6	  	-0.6
	 	  	 Yangpo(3)
	  	 	  	2.1	  	-2.1
	 	  	 Shaping(3)
	  	 	  	1.8	  	-1.8
	 	  	 Jindui(3)
	  	 	  	1.6	  	-1.6
	 	  	 Shicao(3)
	  	 	  	1.4	  	-1.4
	 Zhengzhou
	  	 Shecun
	  	6.0	  	5.9	  	0.1
	 	  	 Dujiagou
	  	2.9	  	2.6	  	0.3
	 	  	 Xiangcaowa
	  	1.4	  	0.9	  	0.6
	 	  	 Jiajiawa
	  	3.8	  	2.1	  	1.6
	 	  	 	  	
	  	
	  	

	 Total
	  	 	  	19.1	  	21.7	  	-2.7
	 	  	 	  	
	  	
	  	




	(1)	Negative figures in the tables indicate that reserves or non-reserve resources this year have increased over last year. 


	(2)	Note the difference between Jiagou (Chinese characters) and Jiagou (Chinese characters). Jiagou (Chinese characters) is a stope owned by the Luoyang mine whereas Jiagou (Chinese
characters) is a jointly operated mine. The pinyin transliteration of both is the same, thus making them easy to confuse. 


	(3)	Shangtan, Yangpo, Shaping, Jindui and Shicao in Table 4(b) are new jointly operated mines added by Chalco in 2003. 

  

 6