In its drive to define the entirety of the Monte Alto deposit, in Brazil, ASX-listed Brazilian Rare Earths has reported more ultrahigh-grade extensions to the south and east of Monte Alto, as well as a priority growth corridor to the north.

In its latest set of drill results from a 10 000 m campaign, the company confirms new intercepts of 25.6 m grading 17.4% total rare earth oxides (TREO), including 8 m of TREO grading 28.1% from 189 m; and 9.4 m grading 21.8% TREO from 161 m, including 6.2 m of TREO grading 25.4% from 162 m.

Having confirmed the high-grade extensions of mineralisation to the south and east of Monte Alto, Brazilian Rare Earths says the north is emerging as a growth corridor, with a targeted 1 400 m drill programme planned for this region. A total 5 000 m drill programme is planned across the northern, southern and eastern growth fronts to continue expanding the mineralised envelope of the Monte Alto deposit.

The latest drill results confirm exceptional rare earth enrichment, with the company reporting neodymium and praseodymium grades up to 66 640 parts per million (ppm), dysprosium oxide grades up to 2 853 ppm, gadolinium oxide grades up to 3 348 ppm, terbium oxide grades up to 471 ppm and yttrium oxide grades up to 27 077 ppm.

Monte Alto is also showing potential for high-grade co-product recoveries, with assays confirming up to 10 986 ppm niobium oxide, 318 ppm scandium oxide, 610 ppm tantalum oxide and 4 443 ppm uranium oxide.

Notably, these latest results were not included in the Monte Alto mineral resource and scoping study production target. Brazilian Rare Earths says the new drilling has expanded Monte Alto's mineralised envelope and remains open to the north, south and east, with new down-dip potential.

Brazilian Rare Earths aims to publish an updated mineral resource estimate by the end of the year.

"The strategic significance is clear. The current Monte Alto production case is based only on drilling available to February 22. Since then, our team has successfully expanded the interpreted mineralised envelope volume to the south and east/down dip, while continuing to deliver ultrahigh grades and advancing the open northern corridor.

"The additional scale immediately strengthens the project’s value proposition and, subject to conversion into mineral resources, could create substantial value through mine-life extension or increased yearly production," says Brazilian Rare Earths CEO and MD Bernardo da Veiga.

Monte Alto forms the anchor deposit for the company's regional Rocha da Rocha project, for which a scoping study earlier this year found an after-tax net present value of $7.9-billion.