The present invention relates to a method and an apparatus for measuring accumulated and instant rate of material loss or material gain of metal elements for the detection of metal deposition (material gain) caused for example during deposition of coatings used in plating processes and corrosion (material loss) caused for example in pipelines during transportation of hazardous media. The apparatus and the method provides means for measuring accumulated and instant rate of material loss or material gain by inserting a probe in a measurement environment causing a probe experience metal deposition or corrosion. Further the apparatus and the method provides means for performing a temperature independent measurement of accumulated and instant rate of material loss or material gain accomplished without use of a temperature sensor device.