Editing Mount Brandon (section)

==Geology==
{{Main|MacGillycuddy's Reeks#Geology}}

Brandon is composed of sandstone particles of various sizes collectively known as ''[[Old Red Sandstone]]''.<ref name="jimr">{{cite book | last1 = Ryan | first1 = Jim | title = Carrauntoohil and MacGillycuddy's Reeks: A Walking Guide to Ireland's Highest Mountains | publisher = Collins Press | isbn = 978-1905172337 | year = 2006 }}</ref> Old Red Sandstone has a purple–reddish colour, and has virtually no fossils.<ref name="jimr"/><ref name="MAS">{{cite web|url=http://www.keepirelandopen.org/Reeks_Report.pdf|title=MacGillycuddy Reeks Mountain Access Development Assessment|publisher=South Kerry Development Partnership|date=December 2013|access-date=29 October 2018|archive-date=20 October 2021|archive-url=https://web.archive.org/web/20211020011519/http://www.keepirelandopen.org/Reeks_Report.pdf|url-status=dead}}</ref> The colour gave its name to nearby [[Purple Mountain (Kerry)|Purple Mountain]].<ref name="jimr"/> The composition of ''Old Red Sandstone'' is variable and contains quartz stones, mudstones, siltstones, and sandstone particles (conglomerate rock boulders with quartz pebbles are visible).<ref name="jimr"/> They are described by the [[Geological Survey of Ireland]] as the oldest [[Devonian]] rocks in Ireland.<ref>{{cite web|url=https://www.npws.ie/sites/default/files/protected-sites/synopsis/SY000375.pdf|title=Site Name: Mount Brandon SAC|date=12 July 2017|publisher=[[Geological Survey of Ireland]]}}</ref>