It also announced an agreement, worth about US$85 million, to sell its Gualcamayo mine in Argentina to Mineros SA.
The Latin American producer has separately gained the option to earn up to 51% of Yamana's La Pepa project in Chile by spending $20 million on exploration over four years and paying $5 million in cash.
In a translated statement, Mineros said the Gualcamayo transaction was an important advance in the company's growth strategy to increase gold production to 500,000 ounces per year.
Gualcamayo was expected to produce 110,000oz of gold in 2018 and Yamana has long been considering a sale as part of its portfolio prioritisation.
Meanwhile, Yamana has increased its gold production guidance from 900,000 to 920,000oz for the year, thanks to strong production including the recent start-up of Cerro Moro in Argentina.
It said the increase should "more than offset" lower than expected silver production, with guidance of 8.15 million ounces reduced to 7.55Moz due to lower than planned production from El Peñón.
It upped its full-year copper guidance from 120Mlb to 125Mlb due to Chapada's performance and forecast improvements into the fourth quarter.
The mine produced 28.6Mlb of copper during the September quarter, down from 37.1Mlb in the previous corresponding period.
Yamana expected all-in sustaining costs to be below guidance due to higher production, operational efficiencies and the impact of local currency depreciation.
The company reported a net loss of $81.3 million, or 9c per share, for the September quarter and said the most notable item was a non-cash accounting carrying value reduction of $75 million on an after-tax basis relating to the Gualcamayo sale.
It adjusted earnings were $23.6 million or 2c per share, compared with $29.1 million and 4c/share a year ago.
The company produced 279,464 gold-equivalent ounces in the third quarter and expects to achieve its gold-equivalent guidance for the year.
It declared a fourth-quarter dividend of half-a-cent per share.
Yamana shares have eased from C$4.68 in January to a 12-month low of $3.03 last month.
They last traded at $3.05, capitalising it at $2.9 billion.
