Unico Silver (ASX:USL) said it reduced the number of drill rigs under its drilling operations in Argentina to two from three as it moves into reduced winter operations, according to a Friday Australian bourse filing.

The company plans to update the Joaquin project mineral resource estimate in the June quarter to incorporate recent infill drilling.

In the same filing, the company said it is conducting pre-feasibility work streams, including geotechnical drilling and interpretation to define open-pit slope and design parameters, as well as comminution and metallurgical test work to confirm processing assumptions and recovery pathways.

The company's shares fell past 1% in recent trading on Friday.