The Rio Tinto river in Spain crosses an ancient mining site which makes the water turn a variety of bright colours. Copper, silver and gold are mined here, as well as iron, which turns the water red. An ochre mix is responsible for the yellow tint of the rest of the river. (Photo by Olivier Jarry-Lancombe/Solent News)

A Ukrainian police officer takes cover in front of a burning building that was hit in a Russian airstrike in Avdiivka, Ukraine, Friday, March 17, 2023. (Photo by Evgeniy Maloletka/AP Photo)

Three workers demonstrating the different types of gas masks used in mine rescue work. (Photo by Fox Photos/Getty Images). December 1925

A clothing shop displays its merchandise in the rebel-controlled city of Idlib, Syria November 7, 2015. (Photo by Ammar Abdullah/Reuters)

Two men fight in San Jose, Costa Rica, during the Women's Day on March 8, 2014. (Photo by Jeffrey Arguedas/EFE/SIPA Press)

A student runs for cover as riot police clash with students during a demonstration on February 29, 2012 in Barcelona, Spain. Student associations have called upon 120,000 students to strike in protest against education cuts recently announced by the Catalan government. (Photo by David Ramos/Getty Images)

Riot police hold their weapons during a protest by supporters of Kenyan opposition National Super Alliance (NASA) coalition, along a street in Nairobi, Kenya on October 11, 2017. Opposition leader Raila Odinga, has called for protests this week, reiterated that he would not take part in a re- run of the presidential election on October 26, 2017 if his demands are not met, as Kenya' s Supreme Court last month overturned the August election of President Uhuru Kenyatta citing “irregularities” in the counting of results. (Photo by Thomas Mukoya/Reuters)