Mercury in crude gold has been determined directly without separation by AAS with potassium thiocyanate as the masking reagent for gold and SnCl_2as reductant to reduce mercury into the vapour atomic mercury in NaOH medium.

• 以硫氰酸甲作金的掩蔽剂,用SnCl_2在强碱介质中还原化合汞为原子汞进行汞的冷原子吸收测定。