** Shares of Riversgold RGL.AX soar as much as 45.7% to
A$0.05, their best day since May 18
** The mineral explorer says it has secured an option to buy
80% lithium rights of a tenement that is east of the Mt Holland
lithium mine in Western Australia urn:newsml:reuters.com:*:nFWN3012HJ
** Co says tenement seen as highly prospective for lithium
in spodumene rich pegmatites
** Shares hit highest since May 23
** Stock has risen more than two-fold this year as of last
close
(Reporting by Archishma Iyer)
((Archishma.Iyer@thomsonreuters.com;))