LESSON 13

Question 1

generally whitish, powdery or whiskers-like crystals on the surface. Efflorescence’s are generally poorly cohesive and commonly made of soluble salt crystals

Answer 1

Encrustation

Question 2

Thin covering or coating layer generally of organic nature, generally homogeneous, follows the stone surface. May be opaque or translucent

Answer 2

Film

Question 3

Generally adhering to but not penetrating into the substrate, possibly changing surface properties (aspect, colour, permeability of the stone

Answer 3

Film

Question 4

Aspect of a surface that reflects totally or partially the light, the surface has a mirror-like appearance

Answer 4

Glossy aspect

Question 5

Engraving, scratching, cutting, or application of paint, ink, or similar matter on the stone surface.

Answer 5

Graffiti

Question 6

generally the result of an act of vandalism. however some may have historical, aesthetics or cultural values and should be conserved

Answer 6

Graffiti

Question 7

Chromatic modification of material, generally resulting from natural or artificial ageing and not involving most cases visible surface deterioration

Answer 7

Patina

Question 8

Sub-types of Patina

Answer 8

1. Iron rich patina
2. Oxalate patina

Question 9

Natural black to brown thin layer enriched in iron/clay materials, which can be found on iron containing sandstones. This kind of patina may be found in outdoor environment, often marble and limestones substrates

Answer 9

Iron rich patina

Question 10

Orange to brown thin layer enriched in calcium oblates. This kind of patina may be found in outdoors environment, often on marble and limestone substrates

Answer 10

Oxalate patina

Question 11

Deposit of a very thin layer of exogenous particles (eg. soot) giving a dirty appearance to stone surface

Answer 11

Soiling

Question 12

The substrates structure is not considered as affected. May have different degrees of adhesion to the substrate

Answer 12

Soiling

Question 13

Deposit, which has a visible thickness, and not systematically a dirty appearance

Answer 13

Soiling

Question 14

With increasing adhesion and cohesion, this can transform into a crust. May originate from atmospheric pollutants (industrial domestic, or car exhaust products) or from particles transported by running water or heating convection

Answer 14

Soiling

Question 15

Poorly adhesive soluble salts, commonly white, located under the stone surface

Answer 15

Subflorescence

Question 16

Hidden, unless the stone layer over them detaches. In that case, salt crystals become visible on the newly exposed surface

Answer 16

Calorescences