Effect of laser cleaning on granite color

by Carlota M. Grossi, Francisco Javier Alonso, Rosa M. Esbert, Araceli Rojo
Color Research and Application ()


This article presents the effect of laser radiation on the color of ornamental granites used for external cladding. The laboratory experimentation was undertaken on a widely used coarse-grain granite commercially known as Rosa Porrin?o. The irradiation was carried out with a Q-switched Nd:YAG laser at 1064 nm and several energy densities (fluences) on polished surfaces, dry and wet, uncoated, and artificially coated-simulating a black crust. Laser effects on the granite surface were determined by color measurements with a colorimeter. These measurements made possible to determine probable damage due to laser radiation and the diverse response of different minerals. The analysis of the data also suggests potential causes for the color change and applicability limits of the technique. The a*-parameter, or red-green component, is the most affected, leading to a change in hab (hue) and was interpreted as a result in variations in the Fe compounds, which strongly condition stone color. No significant changes in L* (luminosity or lightness) or Cab* (chroma) may indicate no relevant alterations in the surface polish. When using laser irradiation to remove black layers on granite surfaces, variations of L* can be indicative of the cleaning effectiveness. This research results nwy be useful to select laser parameters when managing ornamental granite cleaning operations. However, they also suggest the need of further experimentation in specific techniques of analysis as well as different laser wavelengths. © 2007 Wiley Periodicals, Inc.

Cite this document (BETA)

Readership Statistics

11 Readers on Mendeley
by Discipline
by Academic Status
36% Professor
9% Researcher (at a non-Academic Institution)
9% Other Professional
by Country
9% Spain
9% Finland
9% United States

Sign up today - FREE

Mendeley saves you time finding and organizing research. Learn more

  • All your research in one place
  • Add and import papers easily
  • Access it anywhere, anytime

Start using Mendeley in seconds!

Sign up & Download

Already have an account? Sign in