Within these lesions, fibrillar forms of tau contain only 3R isoforms and exhibit a unique cross-sectional core structure.(1) In about 10% of Pick’s disease cases, including the one we report on here, there is additional Alzheimer’s disease pathology, indicated by the presence of neurofibrillary tangles (NFTs).(2) The presence of Pick bodies and NFTs within a single tissue section provided the opportunity to compare the properties of two different forms of tau inclusion using an advanced set of μXRD and μXRF tools. The gene discussed is MAPT; the disease is early-onset autosomal dominant Alzheimer disease.