** Shares of RareX Ltd REE.AX jump as much as 44.7% to
A$0.068 - set for best day since Jan. 20, 2022, if gains holds
** Rare earths explorer upgrades mineral resources estimate
(MRE) for its Cummins Range Rare Earths Phosphate project in
Western Australia
** Co notes six-fold increase from 2021 MRE, with
"appreciable" quantities of niobium and scandium
** RareX at its highest level since Feb. 6
** Stock down ~13% this year, as of last close
(Reporting by Ayushman Ojha in Bengaluru)
((Ayushman.ojha@thomsonreuters.com;))