Materials

Materials are reported in two categories: raw materials, which are the ore from which we extract product, and associated process materials, which are used in processing but are not part of the final product.

Raw Materials

We extract ore, a non-renewable resource, from open pit and underground mines. This ore is either processed through a mill or placed on a heap leach pad to extract the product. In 2016, we processed 54.8 million tonnes (Mt) of ore, compared with 70.7 Mt in 2015.

Associated Process Materials

To process ore and extract metals, our operations use certain materials and reagents such as lime and cyanide, as shown in the table below.

Associated Process Materials and Recycled Input Materials1

2016 2015 2014 2013

Cyanide (t)

30,900

30,800

23,100

26,500

Lime (t)

48,800

83,500

86,200

180,600

Sodium metabisulphite (t)

5,200

3,300

4,000

3,900

Grinding balls (t)

36,800

36,400

28,500

39,800

Other reagents (t)

125,200

57,400

56,800

61,800

Total (t)

246,900

211,400

198,600

309,100

Recycled Input Materials

Recycled input materials used at our mines include mainly waste oil, used grinding balls, fly ash and biosolids. These recycled materials are all sourced internally. Recycled input materials as a percentage of our total tracked input materials (excluding raw materials and fuel) remained constant at 4% in 2016.

2016 2015 2014 2013

Recycled glass (t)

10

0

0

0

Recycled fly ash (t)

8,700

7,500

10,300

11,200

Used oil (t)

100

150

500

1,000

Used liner (t)

0

0

100

100

Biosolids (t)

90

200

7,200

95,100

Other recycled materials (t)

2,000

1,200

2,200

4,900

Subtotal, recycled (t)

10,900

9,050

20,300

112,300

Total, all materials (t)

257,800

220,500

218,900

424,900

Percent from recycled

4%

4%

9%

26%