Mortar
Mortar
Mortar – an important and widely used building material – is available in many different compositions and with various organic tempering materials. Especially the Romans were known for their mortar production and use thereof, so that these mortars were also reused in later times. The basic composition is characterized by sediment, especially sand and lime. Often bone splinters or charcoal are also found in the mortars.
Sample properties
Depending on the dating method, different conditions must be observed when the mortar samples are delivered.
14C-dating
For 14C dating, it is permitted to exposed the mortar to light and to be dried. It is recommended to sort out organic admixtures such as charcoal etc. These are commonly used for dating mortar. A quantity of 20-30 mg is required.
It is possible to date the carbonates of the mortar itself. In those cases please get in touch with the laboratory since certain pitfalls of this kind of dating method are to be considered. Often several partial samples need to be analyzed which would all considered as individual samples.
Luminescence dating
For luminescence dating, it is recommended to draw drill cores due to the low quartz content and remove the exposed surface in the dark. The samples must be pit moist and packed both air- and lightproof (e.g. in aluminium foil and black bags).
Due to the low quartz content, a sample quantity of 100 – 200 g of unexposed (!) material is required, as described above. The exposed material can be used to determine the radioactivity of the mortar itself. This amount would otherwise have to be diverted from the sample. Ideally, the environmental sample, which also needs to be pit moist, consists of a piece of the surrounding masonry.