** Shares of Australia's Petratherm Ltd PTR.AX jump as
much as 40% to A$0.098, highest level since Aug. 8, 2022
** PTR eyes best day since Jan. 31, if gains hold
** Mineral explorer says drill results discovered thick
blanket of "high-grade" rare earth mineralisation at its Comet
project area in South Australia
** Co says project's mineralisation starts at shallow depth
and has potential for additional mineral discoveries
** Stock up 20.7% this year, as of last close
(Reporting by Ayushman Ojha in Bengaluru)
((Ayushman.ojha@thomsonreuters.com;))