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The heavy alteration of archaeological materials makes them environmentally sensitive and, amongst the most challenging, to safely display and store. Non-destructive testing can provide vital information to inform preventive conservation decisions, ensuring the continued preservation of this sensitive material. The heavy chloride contamination of archaeological metals makes some artefacts extremely vulnerable to ambient relative humidities. Copper alloy objects can corrode at RHs above 42 %, whilst some archaeological iron can rapidly deteriorate at RHs above only 19 %. Composite objects with organic components, that will be damaged by low RHs, present a particular challenge. Displays often contain mixed media, and balancing environmental needs between organic artefacts and metals that require low RHs is extremely difficult. A certain proportion of archaeological copper and iron alloys have much lower chloride levels and are relatively stable. Completely mineralised iron artefacts are no longer highly reactive. The challenge is to determine the unstable material within an archaeological metal collection. Radiography, with image processing to identify pits within archaeological iron, has been used to determine the most vulnerable material. Oxygen consumption measurements have been applied to both iron and copper alloy artefacts to measure and predict their reactivity. These analyses have allowed non-reactive material to be displayed safely without environmental control, maximising resources towards the vulnerable material and eliminating the risk to associated artefacts. Architectural stone is expensive to store. A program of reburial on the original sites of durable, low research potential stone has been initiated. Portable x-ray fluorescence and near infra-red spectroscopy has been utilised to identify sandstones and preclude calcite or iron bound sandstones that would be at risk from burial. These techniques are being used, amongst others, to compare the deterioration rates of sandstones in stores and buried.