Concrete has been used as a building material since the Mesopotamian ages and became very popular with Greek and Roman builders. It withstands immense pressure and has a high durability. It can be poured into almost any shape and, when reinforced with steel, it can bridge wide distances. Micro-XRF allows for fast measurements of large areas, with high spatial resolution in short times. The individual element distributions can be visualized and extracted quickly. Fundamental parameter-based quantification allows for a quick assessment of the composition of the sample. Smart analysis of mapping allows for semi-quantitative analysis of Cl and K concentration in the matrix. As concrete is a mixture of many complex chemical compounds its durability depends on environmental conditions. It can last thousands of years under suitable conditions, but nowadays we frequently find images of cracked and weathered concrete. Saltwater, for example, leads to chemical reactions that change the volume and lead to stress and strain in the concrete structure.