Buildings and Walls

adobe brick

Be prepared to do the least possible damage to the site, while needing to use heavy power tools under cloak of darkness to extract the sample


Human-made materials from prehistoric and historic building structures can be directly dated with OSL/IRSL:

  • Cement making up the brick or block, i.e.:
    • Tabby walls and floor  – cement made from coastal sands and oyster shells
    • Adobe walls and roofs – made from local sand, clay and organic material
    • Sandy mortar between bricks



Quality checks:

  • Does the sample contain very to fine quartz or feldspathic sand, or silt-sized sediment?
  • Would the material have been well-exposed to light during construction?
  • Has the structure undergone high-heat conditions (i.e. fire) post-construction?
  • Is there enough material available to date?
    • Can the outer few cm be removed from the specimen leaving the inner-most material intact and used for processing?


Materials from up to 30 cm above and below the sample will be used for the dose rate.

If dating bricks – the surrounding mortar will need to be sampled as well for chemical analysis. Vice versa for mortar dating.

Be aware that these can have dose rate complexities if bricks are made from a different material than the mortar, and/or there is a high concentration of carbonate surrounding the sediment used for dating.


Please obtain all proper permits, paperwork and approvals before removing your sample from the archaeological site and submitting it to the laboratory.