A maiden mineral resource estimate has confirmed the huge size of the Sybella rare earth discovery outside Mount Isa, underlining its global significance, according to Red Metal.

It has defined inferred mineral resources of rare earth oxide mineralisation using a range of cut-off grades for the high-value heavy rare earth oxides neodymium and praseodymium (NdPr).

These include:

• 4.795 billion tonnes at 302 ppm NdPr, 28 ppm DyTb (using a 200 ppm NdPr cut-off grade)
• 2.558 billion tonnes at 331 ppm NdPr, 31 ppm DyTb (using a 300 ppm NdPr cut-off grade)
• 801 million tonnes at 356 ppm NdPr, 33 ppm DyTb (using a 340 ppm NdPr cut-off grade)
• 209 million tonnes at 377 ppm NdPr, 34 ppm DyTb (using a 360 ppm NdPr cut-off grade)

“We knew it was going to be big, but this is way beyond our expectation,” Red Metal managing director Rob Rutherford said.

“This giant resource base will enable any future operation to be long-life and run at very significant economies of scale, lowering its unit mining and processing costs.

“Sybella is shaping up as a globally significant source of MREO minerals and has the potential to become a strategically sought-after asset.

“We now have sufficient data to initiate early-stage mining studies and begin funding discussions with governments and potential end users. ”

Related: Drill results flag vast tonnage potential at Sybella

Red Metal believes the Sybella project, about 20km south-west of Mount Isa, hosts a new REO deposit style for Australia, with the key REO minerals appearing to be fluoro-carbonate minerals.

The maiden Sybella mineral resource estimate used assay data on 1778 six-metre composite samples collected down 139 regularly spaced air core and RC drill holes covering an 8.4km by 3km portion of the rare earth oxide-enriched granite at the site.