 However , Roskill <unk> estimates for primary production show that in 2010 China held a 76 @.@ 75 % share of world supply with 120 @,@ 462 tonnes ( 90 @,@ 000 tonnes of reported and 30 @,@ <unk> tonnes of un @-@ reported production ) , followed by Russia ( 4 @.@ 14 % share , 6 @,@ 500 tonnes of production ) , <unk> ( 3 @.@ 76 % share , 5 @,@ <unk> tonnes ) , Canada ( 3 @.@ 61 % share , 5 @,@ 660 tonnes ) , <unk> ( 3 @.@ 42 % share , 5 @,@ 370 tonnes ) and Bolivia ( 3 @.@ 17 % share , 4 @,@ 980 tonnes ) . 
