Abstract: Method for rapid and accurate weight determination of molten metal in a slag-containing bath preferably without any necessity for direct gross weighings in a hostile steel works environment or otherwise, by the addition to the molten bath of a known weight amount of a "trace" element (preferably of a type which is completely diluted in the molten metal, to the practical exclusion of the slag); awaiting the even dispersal of the trace element in the molten metal (aiding the speed of dispersal by promoting a boiling action, if necessary); taking a sample of the molten metal; analyzing the sample to determine the weight percent of trace element in the molten metal (for example by spectrometric analysis); and determining the weight of the metal from the known values of weight of the trace element added and its weight percent in the molten metal after addition.