Chilwa Minerals (ASX:CHW) said heavy mineral sands assays received as a result of a sonic drill program at the Mposa deposit at its Chilwa critical minerals project in Malawi showed the best mineralized zones to date, according to a Tuesday Australian bourse filing.

Significant intercepts from the drilling program included 6.6 meters at 12.1% grade of total heavy minerals from surface and six meters at 15.2% grade of total heavy minerals from surface.

A mineral resource update for the project is expected in the June quarter. The sonic drill rigs were moved to the Mpyupyu deposit, south of the Mposa deposit, and around half of the Mpyupyu program has been completed.

Its shares rose 5% in recent trading on Tuesday.