Editing Brick (section)

==== Influences on colour ====
[[File:London stock brick (bridge).jpg|thumb|Yellow London Stocks at [[London Waterloo station|Waterloo station]]]]
The colour of fired clay bricks is influenced by the chemical and mineral content of the raw materials, the firing temperature, and the atmosphere in the kiln. For example, pink bricks are the result of a high iron content, white or yellow bricks have a higher lime content.<ref name="ReferenceA">{{Cite journal |last1=Almssad |first1=Asaad |last2=Almusaed |first2=Amjad |last3=Homod |first3=Raad Z. |date=January 2022 |title=Masonry in the Context of Sustainable Buildings: A Review of the Brick Role in Architecture |journal=Sustainability |language=en |volume=14 |issue=22 |pages=14734 |doi=10.3390/su142214734 |issn=2071-1050|doi-access=free |bibcode=2022Sust...1414734A }}</ref> Most bricks burn to various red hues; as the temperature is increased the colour moves through dark red, purple, and then to brown or grey at around {{convert|1300|C|abbr=on}}. The names of bricks may reflect their origin and colour, such as [[London stock brick]] and Cambridgeshire White. ''Brick tinting'' may be performed to change the colour of bricks to blend-in areas of brickwork with the surrounding masonry.

An impervious and ornamental surface may be laid on brick either by [[salt glaze pottery|salt glazing]], in which salt is added during the burning process, or by the use of a [[Slip (ceramics)|slip]], which is a glaze material into which the bricks are dipped. Subsequent reheating in the kiln fuses the slip into a glazed surface integral with the brick base.