Dissolution of fluoride complexes following microwave-assisted hydrofluoric acid digestion of marine sediments

► Insoluble fluorides can form during microwave-assisted digestions in HF. ► Fluorides lead to erroneous measurement of certain major elements. ► For some sample matrices accurate data may require a wait of four weeks. ► Post-microwave sample heating can reduce this wait time to six days or less. ► Heating the diluted sample can reduce this wait time by 75% or more.