Cambior Inc.: Zinc Enrichment in Zone 97 of the Langlois Mine.

MONTREAL--(BUSINESS WIRE)--Sept. 1, 1999--

CAMBIOR(ME:CBJ.) (TSE:CBJ.) (AMEX:CBJ)

All amounts in US dollars

Cambior Inc. is pleased to announce positive results from the definition drilling program in Zone 97 of the Langlois mine which commenced in September 1998.

A one-kilometre drift toward Zone 97 was developed to establish a drilling base to define reserves in this higher grade zone. To date, 20 percent of the tonnage of Zone 97 has been covered by definition drilling (12,500 metres; 93 holes) on a 40 m X 40 m grid. A gain of 16 percent of the zinc metal in reserves for that area has been realized as compared to year-end 1998 and 59 percent as compared to the feasibility study of 1994. The definition drilling program has yielded an increase in the zinc grade in the area to 12.2 percent. 6 This represents an increase of 23 percent in grade as compared to the feasibility study and 3 percent as compared to December 31, 1998. The significant increase in the zinc grade in the drilled portion of Zone 97 indicates a net smelter return (NSR) of $72 per tonne compared to $69 per tonne at December 31, 1998 and $60 per tonne as per the feasibility.

                                                   Feasibility
                June 30, 1999  December 31, 1998    Sudy 994
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Drilled area   Prov.&Prob. NSR  Prov.&Prob. NSR  Prov.&Prob. NSR
of Zone 97:    Reserves  ($/t)  Reserves  ($/t)  Reserves  ($/t)
-----------------------------------------------------------------
Tonnes          590,000@    72   526,000@    69   459,000@    60
Grade              12.2 Zn          11.8 Zn           9.9 Zn
 (percent)          0.7 Cu           0.7 Cu           0.7 Cu

Note:  NSR based on long term zinc prices of 55c/lb and copper prices
       of $1.00/lb with smelting costs estimated at $180 per tonne of
       zinc concentrate.

The area located near the western limit of Zone 97 between levels 8 and 12 (see longitudinal section) displays an important zinc enrichment. The 40 drill holes completed on the interior of this area show an average grade of 17.5 percent zinc and 0.7 percent copper over a thickness of 3.4 metres (before dilution). This represents approximately 400,000 tonnes of ore. Several areas show large possible extensions to the zone, particularly to the east between levels 6 and 12 and at depth. A drill hole to level 12 has intersected the zone deeper than expected, to below level 13.

Due to the success of the definition drilling program, an additional 5,000 metres of drilling is planned to be completed before the end of the year on Zone 97. The drilling program will be extended into the year 2000 to define reserves between levels 7 and 11 as well as to identify reserves below level 13. Further drilling is scheduled for 2001 and 2002 to complete the definition of the zone. A second access to Zone 97 will be initiated in 1999 on level 13.

Zone 97, a vertical massive sulfide lens, is located approximately one kilometre east of the shaft. It measures 600 metres vertically and 450 metres horizontally, and plunges approximately 55( to the east. Its thickness varies between 0.5 and 8.5 metres and averages 4.2 metres. The massive sulfide is composed mainly of sphalerite, pyrite and chalcopyrite with associated galena. The hanging wall of the lens is composed mainly of gabbro and felsic rock (rhyolite, volcanoclastics).

The grade of the mined production from Zones 3 and 4 has improved over the last two years from 6.4 percent Zn in 1997 to 7.9 percent Zn in the second quarter of 1999. Further improvements in zinc head grade are expected from Zones 3 and 4 as the mine plan evolves into the higher-grade core of the zone with a grade of 9 percent. The direct mining cost for the first six months of 1999 was $35 per tonne and the NSR was $42 per tonne. The commencement of production from Zone 97, expected in the second half of the year 2000, will provide ore at a grade of 12 percent Zn and will further improve the economics of the Langlois mine.

Cambior Inc. is an international diversified gold producer with operations, development projects and exploration activities throughout the Americas. Cambior is the first gold mining company to receive ISO 14001 certification of its environmental management system. Cambior's shares trade on the Toronto, Montreal and American (AMEX) stock exchanges under the symbol "CBJ".

This press release contains certain "forward-looking statements", as defined in the United States Private Securities Litigation Reform Act of 1995, that involve a number of risks and uncertainties. There can be no assurance that such statements will prove to be accurate and actual results and future events could differ materially from those anticipated in such statements.

Such risks and uncertainties are disclosed under the heading "Risk Factors" in Cambior's Annual Information Form (AIF) filed with the Ontario Securities Commission, the Quebec Securities Commission, the United States Securities and Exchange Commission (Form 40-F) and other regulatory authorities