Quarterly Producton Report - Part 4

RIO TINTO PLC
27 October 1999

Part 4

EXPLORATION

Expenditure

Rio Tinto's pre-tax exploration expenditure charged to the
profit and loss account for the quarter ending 30 September
1999 was $26 million compared with $42 million in the
comparable quarter of 1998. Total expenditure for the first
nine months of 1999 was $90 million compared with $118
million in the first nine months of 1998.

Rationalisation of the global exploration programme continued
with the termination of projects in Laos, Sweden, Spain and
Portugal. The Las Cruces massive sulphide deposit in Spain was
sold for $42 million and divestment decisions were made for
the Sepon copper-gold deposits in Laos and the Palu gold
deposit in Indonesia.

Major Developments

Grasberg, Indonesia

In Block A, dewatering holes intersected new mineralisation
300-400m north of the Kucing Liar skarn. Definition drilling
continued on the Kucing Liar and Deep Grasberg orebodies.

Other Programmes

Country:  Australia
Commodity:  Diamonds
Programme Summary: Deep mine delineation drilling continued at
the Argyle diamond mine.

Country:  Bolivia
Commodity:  Silver
Programme Summary:  Delineation drilling continued at the
Tolloci bulk tonnage silver-zinc prospect.

Country:  Canada
Commodity:  Diamonds
Programme Summary:  Delineation drilling continued on the A180
kimberlite pipe on the Diavik diamond property.

Country:  Peru, Chile
Commodity:  Copper
Programme Summary:  Delineation drilling continued on oxide
copper properties in Peru and Chile. Definition drilling
commenced at the Pukaqaqa sulphide copper-gold prospect in
Peru.


Country:  Zimbabwe
Commodity:  Diamonds
Programme Summary:  Surface bulk sampling continued on three
diamondiferous kimberlite pipes discovered by the Rio Tinto
Zimbabwe/Rio Tinto exploration joint venture.

Regional Programmes

A number of early stage exploration programmes were underway
in various regions.

 All $ are US, unless otherwise stated.