** Shares of Ark Mines AHK.AX fall 8.6% to A$0.160

** Stock set for its weakest session since April 23

** Diversified miner receives commitments to raise A$1.5 million ($959,700) at A$0.14 apiece from two investors

** Issue price represents a 20% discount to co's last close

** Says it can now expedite its rare earth development program at the Sandy Mitchell project in Queensland

** Stock up 14.3% YTD, including current session's moves

($1 = 1.5630 Australian dollars)

(Reporting by Manasi Dasa in Bengaluru)

((Manasi.DasaSundeep@thomsonreuters.com;))