Mass spectrometers are large machines that are kept in very clean surroundings. You won't find one in the field! Archaeologists and other scientists send samples to labs that specialize in using this amazing tool. Mass spectrometers ("mass specs" for short) can determine the chemical composition of samples. This is useful for understanding where the stone for building may have come from or the sorts of foods that ancient people may have been eating. Also, if a sample of organic material can be found (this means something that was once alive), it is possible to figure out the sample's age using radiocarbon (C14) dating! Items like charcoal, bone collagen, wood, seeds, shells, and leather are possible candidates for C14 dating.
