The Valley is covered with mineral deposits that mark the location of extinct fumaroles. Black staining around these spots typically reflect magnetite or hematite. White zones may be enriched in silica and clay minerals. Orange to yellow staining indicates minerals such as limonite, geothite, or sulfur. NPS photo by M. Fitz.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/99350217@N03">Katmai National Park and Preserve</a>
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/katmainps/13542878805/">Colors near Novarupta</a>