Hamar women dance before a bull jumping ceremony in Ethiopia's southern Omo Valley region near Turmi on September 19, 2016. The Hamar are a Nilotic ethnic group in Ethiopia. The construction of the Gibe III dam, the third largest hydroelectric plant in Africa, and large areas of very “thirsty” cotton and sugar plantations and factories along the Omo river are impacting heavily on the lives of tribes living in the Omo Valley who depend on the river for their survival and way of life. (Photo by Carl De Souza/AFP Photo)

A historical re-enactor poses for a photograph in a living history camp as he prepares to take part in an anniversary event for the Battle of Bosworth near Market Bosworth in central Britain August 22, 2015. The Battle of Bosworth took place in 1485 during the War of the Roses between the Houses of Lancaster and the House of York. King Richard III was defeated by Henry Tudor marking the end of Plantagenet rule and the beginning of the Tudor dynasty. (Photo by Neil Hall/Reuters)

The mineral pyrite, or iron pyrite, also known as fool's gold, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fool's gold. The color has also led to the nicknames brass, brazzle, and Brazil, primarily used to refer to pyrite found in coal.
In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals.

Reuters photographer Bobby Yip took a series of portraits of people taking part in the “Occupy Central” protests in Hong Kong, and asked them why they had joined the demonstrations. China rules Hong Kong under a “one country, two systems” formula that accords the territory limited democracy. Tens of thousands of mostly student protesters are demanding Beijing give them full democracy, with the freedom to nominate election candidates. The unrest is the worst in Hong Kong since China resumed its rule over the former British colony in 1997. (Photo by Carlos Barria/Reuters)

In the desert near Joshua Tree, California, there stands a 70-year-old homestead cabin that isn’t all there. The ethereal cabin is part of an outdoor art installation by artist Phillip K. Smith III called Lucid Homestead. To give the cabin its striking appearance, the artist replaced strips of the wall with mirrors and the windows with mirrored panels that light up at night. The building reflects the desert sun and environment around it, making it seem like an airy and transparent space

People take part in the “The Burial of the Sardine” funeral procession, which marks the end of carnival festivities, in Madrid, Spain, February 10, 2016. “Mourners” carry a coffin with a mock sardine through the streets to celebrate the countdown to Lent. Spanish painter Francisco de Goya's painting “El entierro de la sardina” (The Burial of the Sardine) was inspired by this tradition, which started in Madrid in the 18th century, around the time of Spanish King Carlos III. (Photo by Juan Medina/Reuters)

Mexicans dressed as French soldiers carry handcrafted guns, ahead of a reenactment of the battle of Puebla between Zacapoaxtla Indians and the French army during Cinco de Mayo celebrations in Mexico City, Tuesday, May 5, 2015. Monsalvo said he has been portraying Napoleon III in the annual neighborhood event for 28 years. Cinco de Mayo commemorates the victory of an ill-equipped Mexican army over French troops in Puebla on May 5, 1862. (Photo by Rebecca Blackwell/AP Photo)

In this March 7, 1991 file photo, a U.S. Marine patrol walks across the charred oil landscape near a burning well during perimeter security patrol near Kuwait City. Twenty five years after the first U.S. Marines swept across the border into Kuwait in the 1991 Gulf War, American forces find themselves battling the extremist Islamic State group, born out of al-Qaida, in the splintered territories of Iraq and Syria. The Arab allies that joined the 1991 coalition are fighting their own conflicts both at home and abroad, as Iran vies for greater regional power following a nuclear deal with world powers. (Photo by John Gaps III/AP Photo)