 A few large deposits produce or produced a significant amount of the world production . The Bayan Obo iron ore deposit contains significant amounts of bastnäsite and monazite and is , with an estimated 36 million tonnes of rare earth element oxides , the largest known deposit . The mining operations at the Bayan Obo deposit made China the largest supplier of rare earth elements in the 1990s . Only 0 @.@ 2 % of the rare earth element content is europium . The second large source for rare earth elements between 1965 and its closure in the late 1990s was the Mountain Pass rare earth mine . The bastnäsite mined there is especially rich in the light rare earth elements ( La @-@ Gd , Sc , and Y ) and contains only 0 @.@ 1 % of europium . Another large source for rare earth elements is the loparite found on the Kola peninsula . It contains besides niobium , tantalum and titanium up to 30 % rare earth elements and is the largest source for these elements in Russia . 
 A few large deposits produce or produced a significant amount of the world production . The Bayan Obo iron ore deposit <a href='uninflect' title='1'><mark>contains</mark></a> significant amounts of bastnäsite and monazite and is , with an estimated 36 million tonnes of rare earth element oxides , the largest known deposit . The mining operations at the Bayan Obo deposit made China the largest supplier of rare earth elements in the 1990s . Only 0 @.@ 2 % of the rare earth element content <a href='drop_aux' title='2'><mark>is</mark></a>europium . The second large source for rare earth elements between 1965 and its closure in the late 1990s was the Mountain Pass rare earth mine . The bastnäsite mined <a href='dey_it' title='3'><mark>there</mark></a> is especially rich in the light rare earth elements ( La @-@ Gd , Sc , and Y ) and <a href='uninflect' title='4'><mark>contains</mark></a> only 0 @.@ 1 % of europium . Another large source for rare earth elements <a href='drop_aux' title='5'><mark>is</mark></a>the loparite found on the Kola peninsula . It <a href='uninflect' title='6'><mark>contains</mark></a> besides niobium , tantalum and titanium up to 30 % rare earth elements and <a href='drop_aux' title='7'><mark>is</mark></a>the largest source for these elements in Russia . 
A few bigass deposits produce or produced a significant amount of the world production . The Bayan Obo iron ore deposit contain significant amounts of bastnäsite and monazite and is , witt an estimated 36 million tonnes of rare earth element oxides , the largest known deposit . da mining operations at tdaBayan Obo deposit made China the largest supplier of rare earth elements in the 1990s . Only 0 @.@ 2 % of the rare earth element content europium . The secondbigasse source fa rare earth elements between 1965 and its closure in thdaate 1990s was the Mountain Pass rare earth mines . Thedastnäsite mined it is especially rich in the light rare earth elements ( La @-@ Gd , Sc , and Y ) and contain only 0 @.@ 1 % of europium . Anothebigassge source ffirrare earth elements the daarite found on the Kola peninsula . It contain besides niobium , tantalum and titanium up to 30 % rare earth elements and the largest source for dem elements in Russia .