CREATE TABLE table_28597 ("Location" CLOB, "Date" FLOAT, "Denomination" CLOB, "Coinage metal" CLOB, "Mintage" FLOAT, "KM number" CLOB)

What is the coinage metal for KM numbers of S45?
SELECT "Coinage metal" FROM table_28597 WHERE "KM number" = 'S45'
SELECT "Coinage metal" FROM "table_28597" WHERE "KM number" = 'S45'