The technique requires that the operator have considerable experience and skill so that the stone surface itself is not abraded.
The stone surface treatment with water jet is a recently introduced method.
It's biofilm — a microbial invasion of uncertain origin that has begrimed the stone surface of one of the nation's most hallowed monuments.
The poultice is then removed from the stone surface and the process repeated until all, or an acceptable amount, of the salts present are removed.
Freeze-thaw cycles can result in spalling, or delamination of the stone surface, eventually leaving no more than a shapeless mass in a relatively short amount of time.
On closer inspection, Ines saw that jewels had been placed in crevices, and sharpened pins like medieval cloak brooches had been inserted in holes threaded in the stone surface.
The addition of TiO2 to the polymer was found to decrease the color impact of the coatings on the stone surface.
The most effective methods of stone processing that protect the stone surface and maximum preservation of gloss and lightness for different aggressive environments were determined.
The firm behind the design, 1100 Architect, says on its Web site that the "gradual shifts of color within the stone surface" create a "delicate" yet "distinguished" presence in the area.
For lithographic prints a plain dark-coloured crayon made of wax, soap, lac, mastic, sheep tallow, lampblack, and sometimes copal is used to draw an image directly on the stone surface.
An infrared camera measured: (a) the moisture stain due to the water absorption after having spilled a drop on the stone surface and (b) the "moisture ring" around the damp surface, after the contact between a soaked round sponge and the stone surface.
