Seafloor hydrothermal deposits (also referred as seafloor massive sulfide deposits, or SMS deposits) are plentiful in the waters off of Japan. SMS deposits are promising mineral resources for resource‐poor Japan. A joint venture of Mitsubishi Heavy Industry (MHI) (the representative of the JV), Kayaba System Machinery Co., Ltd., and Sumitomo Metal Mining Co., received an order of a Mining element engineering test machine to collect technical data necessary to construct SMS mining systems. The test machine was constructed in March 2012 and delivered to Japan Oil, Gas and Metals National Corporation (JOGMEC). We conducted an offshore examination with this test machine to excavate an SMS deposit at the bottom of the sea in Okinawa's waters in Nov. 2012 and successfully collected the samples by using a slurry pump.
