25D13(GOLD) · minerals and metals: gold

25D35 · smelting, extracting from ore; blast-furnace

25H114 · low hill country

31A22210 · heart symbolism

41A775 · wooden container: barrel, cask

41B1 · open fire (in general)

41B1311 · bellows

47A122 · blast-furnace

47C242 · vertical transport, hoisting (industrial processes)

49E9 · experiment, test ~ science and technology

86(ΠΆΘΗΜΑ ΜΆΘΗΜΑ) · proverbs, sayings, etc. (ΠΆΘΗΜΑ ΜΆΘΗΜΑ)