Elevate Uranium (ASX:EL8) said its U-pgrade pilot plant processing ore from its Marenica uranium project in Namibia has achieved cumulative mass rejection of about 88% of original ore mass using stages one to four, in line with the design and confirming historical bench-scale testing in 2013, according to a Monday Australian bourse filing.

The company said uranium recovery of 79% has been reported using stages one to four, in line with expectations, with an upgrade ratio of seven times achieved, also in line with the ratio at the equivalent point in historical bench-scale testing.

A further six to eight times increase in grade was demonstrated from stage five in historical bench-scale testing, with results to be incorporated into a Marenica Scoping Study work program, the filing added.

The company's shares fell 7% in recent Monday trade.