The company is the ASX-listed ABx Group Limited, chaired by former Tasmanian Labor premier Paul Lennon.

The ABx Group told the ASX a 97-hole exploration drilling program had enlarged a high-grade rare earth elements zone and confirmed the exploration target area was bigger than 100 square kilometres.

The company said the drilling results showed the target area was highly enriched in dysprosium and terbium, the two rare earths with the most "critical supply risk".

Rare earths have many uses, including in batteries for electric and hybrid vehicles, smart phones, computers, light globes and televisions.

The ABx Group said the exploration results from its Rubble Mound rare earths zone maintained the highest proportion of dysprosium and terbium of any clay-hosted rate earths resource in Australia and it was very high by global standards.

The drilling campaign that ran from January 15 to March 6 was the first for rare earth elements at the Rubble Mound zone.

It had previously only been drilled for shallow bauxite zones.

The company said the area was part of the "extensive, 52 million tonne Deep Leads-Rubble Mound resource".

Managing director and chief executive Mark Cooksey said it was exciting that the exploration program was continuing to produce outstanding results.

"A focus of the recent drilling campaign was to expand the Rubble Mound high-grade zone within the existing resource and this has been achieved," Dr Cooksey said.

"We look forward to providing the remainder of the assay results from this drilling campaign and a resource update, which will include Wind Break for the first time."

The resource at the Wind Break zone is expected to be estimated during April.