 Most methods are non-destructive in nature, such as X-ray spectroscopy, or micro-destructive (requiring removal of only a tiny portion of the sample).Non-destructive methods can be used on more artefacts than destructive ones, but because they operate at the surface of the metal, corrosion and other surface effects may interfere with the results.Options that include sampling include various forms of mass spectrometry and a variety of chemical tests.