What are the cost prices of large burnished copper?
cost price refers to ps_supplycost; large burnished copper refers to p_type = 'LARGE BURNISHED COPPER'
SELECT T2.ps_supplycost FROM part AS T1 INNER JOIN partsupp AS T2 ON T1.p_partkey = T2.ps_partkey WHERE T1.p_type = 'LARGE BURNISHED COPPER'