It said yesterday it expected operations would reach "normal levels within the following hours" and had restarted exploration drilling.
It reduced its forecast production from 20-21 million pounds of copper to 17-18Mlb, and from 10,200-10,700 ounces of gold to 9,000-9,700oz.
It had achieved its highest annual production in 2018 of 21.87Mlb copper and 11,344oz.
"Throughout the remainder of the year, the company will make every operational effort to make up for as much lost production as possible," Atico said.
The strike began in February when negotiations over a collective agreement failed.
It had a significant impact on Atico's first quarter production, with copper and gold output down by 57% and 45% respectively on a year earlier.
Once the strike passed its 60th day on April 12, Atico had said Colombian law dictated a legal process to end it through arbitration.
Atico shares closed down 6.9% or C2c yesterday to 27c, close to its 52-week low reached in December, capitalising it at $26.6 million.
