Leopard seal chasing a Gentoo penguin in Antarctica. This image wins the gold prize in the behaviour – mammals category, and the grand prize of World Nature Photographer of the Year. (Photo by Amos Nachoum/World Nature Photography Awards)

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.

The Jet Propulsion Lab team's RoboSimian robot turns on a valve at a simulated disaster-response course during day one of the Defense Advanced Research Projects Agency (DARPA) Robotics Challenge finals in Pomona, California, June 5, 2015. (Photo by David McNew/Reuters)

In advance of Fleet Week performances, the U.S. Navy Blue Angels and Team Oracle aerobatics pilot Sean D. Tucker fly over the San Francisco Bay during a photo flight on Thursday, October 5, 2017. (Photo by Noah Berger/AP Photo)

Visitors, wearing face masks, enter the Disneyland theme park in Shanghai as it reopened, Monday, May 11, 2020. Visits will be limited initially and must be booked in advance, and the company said it will increase cleaning and require social distancing in lines for the various attractions. (Photo by Sam McNeil/AP Photo)

One of the most significant challenges related to cancer in Nepal is the lack of awareness around the prognosis of the disease, as many patients, their families and even healthcare professionals consider cancer to be an incurable disease at any stage. This results in significant delays in bringing patients to hospitals, and high rates of advanced stage cancers and mortality. (Photo by Omar Havana)

A man helps an elderly woman to run for cover after heavy shelling on the only escape route used by locals, while Russian troops advance towards the capital, in Irpin, near Kyiv, Ukraine on March 6, 2022. (Photo by Carlos Barria/Reuters)

English actress Diana Rigg as “Emma Peel” is tied to a railway track as a miniature train advances on her in a scene from the television series “The Avengers” in 1968. Rigg died at her home in London on 10 September 2020, at the age of 82. (Photo by Popperfoto via Getty Images/Getty Images)