Cores4n s.r.l. is able to carry out part of the diagnostics on its own. Our laboratory is equipped with a Polar Nikon Eclipse E50i Pol microscope equipped with an image acquisition system (Nikon camera) and ISOMET LSS mitre saw. For the analysis in situ and in progress, it has adequate portable instrumentation that allows the observation of surfaces, the collection of images in high-magnification digital microscopy, both in reflected white light and in UV. Additional portable instrumentation available consists of a Flir thermal imaging camera, fiber optic endoscope, UV lamps, salinometers, hygrometers and various digital photographic equipment.
Microscopic observations of plaster samples
Geometric survey with localization on the prospect of the photograph with its alphanumeric reference code
Photo of the south prospectus (P.S.F1) showing the area where the micro-photos were made
Bio films and biological crusts observed in digital microscopy on painted surfaces
Scanning of the surface in Photomicrograph of the south prospectus: P.S.M1 photo made in reflected light. P.S.M2 photo made in grazing light.
Normally the formation of biofilm on stone surfaces begins with bacteria and phototrophic microorganisms (algae, cyanobacteria) considered pioneer organisms on whose metabolites, exploited as a carbon source, heterotrophic microorganisms settle thus giving rise to the development of the biofilm whose composition is very complex and articulated. The characterization takes place through optical microscopy techniques for a preliminary identification of the samples and in SEM scanning electron microscopy. Any further investigations, if necessary, can be performed with the aid of different molecular biology techniques.
MIA3 sampling point and observation of the surface in digital microscopy before treatments
|MIA2||stone material fragment with brown-black surface patina||cell||SL|
|MIA3||stone material fragment with brown-black surface patina||cell||SS, SS-EP|
Tab 1 – Legend: SL= optical microscope observation of shiny sections; SS = observation of thin sections under an optical microscope in polarized light; SS-EP= optical microscope observation of thin sections with episcopic illumination
MIA3 sample in shiny section, a brown-black surface patina can be observed
(5x magnification) (20x magnification)
MIA3 sample – the analysis of the thin section in episcopic light allows to identify the points where biological aggression penetrates inside the material, weakening the intercrystalline bonds.
The nicolcrossed analysis confirms that the nature of the material infiltrated between the crystalline edges of the marble is not of the crystalline type, but that it is attributable to a material of biological origin (10x magnification).
Example of verification carried out during a bio-cleaning operation with desulfating bacteria.
Ongoing verification of a biocide treatment
Digital microscopy control of the marble surface after a preliminary biocide treatment
Control of the same surface after a second treatment
Control of the same surface at the end of the treatment