Editing Ultramarine (section)

== Synthetic applications ==
Synthetic ultramarine, being very cheap, is used for wall painting, the printing of paper hangings, and [[calico]]. It also is used as a corrective for the yellowish tinge often present in things meant to be white, such as [[linen]] and [[paper]]. [[Bluing (fabric)|Bluing]] or "laundry blue" is a suspension of synthetic ultramarine, or the chemically different [[Prussian blue]], that is used for this purpose when washing white clothes. It is often found in makeup such as [[mascara]]s or [[eye shadow]]s.<ref name="EB19112" />

Large quantities are used in the manufacture of paper, and especially for producing a kind of pale blue writing paper which was popular in Britain.<ref name="EB19112" /> During World War I, the [[Royal Air Force|RAF]] painted the outer [[roundel]]s with a color made from ultramarine blue. This became BS 108(381C) aircraft blue. It was replaced in the 1960s by a new color made on [[phthalocyanine blue]], called BS110(381C) roundel blue.{{cn|date=December 2023}}