Singer Madonna performs during her concert at the AccorHotels Arena in Paris, France, December 9, 2015, on her Rebel Heart Tour. (Photo by Benoit Tessier/Reuters)

A couple takes selfie pictures amid heart shaped decorations setted for Valentine's day, in Bangkok, Thailand on February 14, 2021. (Photo by Mladen Antonov/AFP Photo)

A woman carries a heart shaped balloon while sitting with her husband on a motorbike during Valentine's day, in Karachi on February 14, 2021. (Photo by Rizwan Tabassum/AFP Photo)

The Britain’s Got Talent host Amanda Holden, 48, showed off her flexibility in knee-high boots in the corridors of Heart FM in London, England on February 3, 2020. (Photo by The Sun)

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.

A woman eats candy in the shape of a phallus during the Kanamara Matsuri, or Iron Phallus Festival through a street near the Kanamara shrine in Kawasaki outside of Tokyo April 5, 2015. The festival celebrates fertility and is used to raise awareness and money for the prevention of sexually transmitted diseases. (Photo by Thomas Peter/Reuters)

Girls play in the makeshift refugee camp at the northern Greek border point of Idomeni, Greece, Thursday, March 17, 2016. Leaders of the EU's 28 divided nations reconvene in Brussels in hopes of ironing out disagreements on a proposed agreement with Turkey in the migrants crisis. (Photo by Vadim Ghirda/AP Photo)