The restart followed engagement with the United Mineworkers' Union and the Sierra Leone government.
"While some level of uncertainty persists, discussions with the union are ongoing and a process has been agreed to resolve the unlawful strike," Iluka said.
Sierra Rutile's initial 2018 guidance, set at the start of the year was 160,000 tonnes of rutile.
It was downgraded in July to 145,000t due to lower mining rates and again to 135,000t when the strike was first reported last week.
Today Iluka reported that likely maximum production for 2018 would be 125,000-130,000t, but that assumed a quick ramp-up and improved operational performance this quarter.
The operation produced 93,400t in the first nine months of the year.
Shares in Iluka opened A2c lower at $8.03.