sarooj

{{Short description|Type of mortar}}

{{Expand Farsi|ساروج|date=April 2021}}

{{Expand Arabic|صاروج|date=April 2021}}

Sarooj is a traditional water-resistant mortar used in Iranian architecture,{{cite book|author=Peter Jackson|title=A Windtower House in Dubai|url=https://books.google.com/books?id=-vA8AAAAMAAJ|year=1975|publisher=Art and Archaeology Research Papers|page=8}}{{cite book |author=Bernhard Glaeser |title=Learning From China?: Development and Environment in Third World Countries |url=https://books.google.com/books?id=Dfq3AAAAQBAJ&pg=PA227|date=5 September 2013 |publisher=Routledge |isbn=978-1-136-88103-9 |pages=227–}} used in the construction of bridges{{cite book|author1=Changkuan Zhang|author2=Hongwu Tang|title=Advances in Water Resources & Hydraulic Engineering: Proceedings of 16th IAHR-APD Congress and 3rd Symposium of IAHR-ISHS|url=https://books.google.com/books?id=UjxkGG4feEQC&pg=PT994|date=28 July 2010|publisher=Springer Science & Business Media|isbn=978-3-540-89465-0|pages=947–949}} and yakhchāl, ancient Persian ice houses.[http://www.ijesd.org/papers/238-B094.pdf The Earth Refrigerators as Earth Architecture] at IJESD.org

It is made of clay and limestone mixed in a six-to-four ratio to make a stiff mix, and kneaded for three days.{{citation needed|date=September 2019}} A portion of furnace slags from baths is combined with cattail (Typha) fibers, egg, and straw, and fixed, then beaten with a wooden stick for even mixing. Egg whites can be used as a water reducer as needed.

Its origin (in Persian: Saru) is lime, i.e. limestone mixed with arsenic.{{Cite book |last=القس طوبيا العنيسى الحلبي اللبناني |url=https://archive.org/details/TOB1932ARAR |title=تفسير الالفاظ الدخيلة في اللغة العربية |date=1932}}