The concentration of fluoride by boiling.
D002124:Calcium Fluoride / Q000032:analysis; D004739:England; D005457:Fluoridation; D005459:Fluorides / Q000032:analysis*; D007503:Iron Isotopes; D008274:Magnesium / Q000032:analysis; D012995:Solubility
D007503:Iron Isotopes; D008274:Magnesium; D002124:Calcium Fluoride; D005459:Fluorides