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.

Ron Mueck's “Big Baby” sculpture appears to look round at Jenny Saville's painting “Interfacing” at the Masterpieces Exhibition at Christie's on June 13, 2011 in London, England. The painting and sculpture feature in the exhibition, open to the public from 13th–15th June 2011, which showcases some of the Ј250 million worth of art for sale over the next four weeks. Artists including Michelangelo, Gainsborough, Goya, Stubbs, Monet, Picasso and Renoir are represented. (Photo by Peter Macdiarmid/Getty Images)

South Korean teenagers participate in a warfare exercise as part of the Special Warfare Command's training course at a military base on August 4, 2011 in Seoul, South Korea. About 1,000 civilian volunteers including middle and high school students participated in the special force's four-day training programme to develop their spiritual and physical strength. (Photo by Chung Sung-Jun/Getty Images)

Protest posters are attached to the walls surrounding the “Occupy London” camp outside St. Paul's Cathedral on November 01, 2011 in London, England. The Dean of St. Pauls Cathedral The Very Reverend Graeme Knowles resigned yesterday over the church's handling of the anti-capitalist “Occupy London” demonstration, which continues to occupy the grounds outside the cathedral. (Photo by Dan Kitwood/Getty Images)

A penguin swims in its enclosure during a photocall to promote London Zoo's annual stock take of animals on January 4, 2012 in London, England. The zoo's stocktake takes place annually, and gives keepers a chance to check on the numbers of every one of the animals from stick insects and frogs to tigers and camels. (Photo by Dan Kitwood/Getty Images)

Anna Nicole Smith at boyfriend Christian Audigier's Hollywood apartment in Hollywood, CA, 1998. (Photo by Paul Harris/Hulton Archive)

Gray whale feeding at the surface and showing it's baleen. (Photo by Christopher Swann/Biosphoto)

Revellers take part in New Year's Eve celebrations in Kyiv, Ukraine on December 31, 2020. (Photo by Valentyn Ogirenko/Reuters)