Brazilian Rare Earths (ASX:BRE) said a high-resolution airborne geophysical survey and reconnaissance diamond drilling at the Velhinhas Corridor in Brazil has defined more than 9 kilometers of cumulative exploration corridor trends, according to a Thursday Australian bourse filing.

The company said the survey extends rare earth mineralization to over 8 kilometers south of the ultra-high-grade Monte Alto Deposit, and ultra-high-grade surface samples returned grades of up to about 40% total rare earth oxide (TREO), 21% TREO, and 14% TREO, confirming a strong high-grade surface expression of an extensive mineralized system.

Reconnaissance diamond drilling returned grades of 20% TREO; 33,607 parts per million (ppm) neodymium-praseodymium (NdPr); 1,463 ppm dysprosium oxide; 248 ppm terbium oxide; 7,431 ppm yttrium oxide; and 1,087 ppm uranium oxide, the filing added.

The survey confirms four north-northeast-trending mineralized corridors, converting numerous ultra-high-grade surface results into a district-scale exploration model, the company said.

Brazilian Rare Earths has mobilized an additional diamond drill rig and is advancing a more than 5,000-meter drilling campaign to test priority geophysical anomalies and expand bedrock mineralization, it added.