Eastplats said the company plans full baseline testing of staff and contractors, as well as additional training and education, to prevent the virus from spreading.
The chrome facility, which reprocesses tailings from subsidiary Barplats Mines, had restarted work on April 8 after the South African government eased restrictions on mining activity.
Eastplats now expects chrome concentrate production to resume there no later than June 20.
"The effects of COVID-19 are changing rapidly and the consequences of the temporary shutdown of Crocodile River are expected to be minimal, however, if it is extended the effects cannot be reasonably estimated at this time but could have material adverse effects on the company's business and cashflows."
The company reported on erly June that revenues had risen 163% year-on-year to US$14.2 million for the first quarter of 2020. The average grade of chrome concentrate was 38.56% and 293,968t of concentrate was processed in the quarter.