Petrography of historic mortar materials: polarising light microscopy as a method for characterising lime-based mortars

Kristin Balksten, Jan-Erik Lindqvist, Bo Nitz, John Hughes

Research output: Chapter in Book/Report/Conference proceedingConference contribution


In studying historic, repair and restoration mortars comprised of lime-based material there is an analytical method that answers more questions than any other; transmitted (and reflected) polarised light microscopy (PLM). The present study is based on thin-section analysis of historic and restoration mortars made by the authors in Sweden and Scotland since the 1980’s, previous research (i.e. Elsen 2005, Blaeuer & Kueng 2007, Middendorf et al 2005, Lindqvist & Sandström 2000) and petrographic atlases (Ingham 2010, MacKenzie, Adams 1994). It is illustrated by a selection of microphotographs to show the variety of questions that the method can give answers to, such as, in the study of:• lime binder; source materials, hydraulicity, slaking methods, lime lumps, cracking tendencies• aggregates; grading, mineralogy/lithology and texture• additives; inorganic puzzolanic materials and organic materials• paint layers; different binders, pigments, thicknesses• pore structure; durability, vapour transport and capillarity• craftsmanship; various application and working techniques The aim of this paper is to illustrate the usefulness of Polarising Light Microscopy as a method for characterising lime-based mortars and to contribute with references on parameters that can be analysed.
Original languageEnglish
Title of host publication5th Historic Mortars Conference. HMC 2019. Book of Abstracts
Subtitle of host publicationUniversity of Navarra, Pamplona. 19th - 21st June, 2019
EditorsJose Ignacio Alvarez Galindo, Jose Maria Fernandez Alvarez, Inigo Navarro Blasco, Adrian Duran Benito, Rafael Sirera Bejarano
Place of PublicationPamplona
PublisherUniversity of Navarra
Number of pages1
ISBN (Print)9788409090778
Publication statusPublished - 19 Jun 2019
Event5th Historic Mortars Conference 2019 - Universidad de Navarra, Pamplona, Spain
Duration: 19 Jun 201921 Jun 2019
Conference number: 5


Conference5th Historic Mortars Conference 2019
Abbreviated titleHMC 2019
Internet address


  • Petrography
  • Thin sections
  • Lime mortar
  • Polarising light microscopy
  • Optical microscopy


Dive into the research topics of 'Petrography of historic mortar materials: polarising light microscopy as a method for characterising lime-based mortars'. Together they form a unique fingerprint.

Cite this