** Shares of Australia's St George Mining SGQ.AX rise as much as 18.2% to A$0.13, their highest since October 21
** Critical minerals explorer reports further exceptional assays of very thick and very high-grade rare earths and niobium mineralisation at Araxá Rare Earths and Niobium Project in Minas Gerais, Brazil
** Around 48.4 mln shares change hands, nearly 2.2x 30-day average
** SGQ up 26.3% YTD
(Reporting by Keshav Singh Chundawat in Bengaluru)
((Keshav.singhchundawat@thomsonreuters.com))