Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO3. In its (rare) pure form, it is typically a rose-red color, but impure specimens can be shades of pink to pale brown. It streaks white, and its Mohs hardness varies between 3.5 and 4. Its specific gravity is between 3.5 and 3.7. It crystallizes in the trigonal system, and cleaves with rhombohedral carbonate cleavage in three directions.

Under Exposed: Pekka Tuuri (Finland) – Great white shark, Isla Guadalupe, Mexico. “Isla Guadalupe is the world capital when it comes to observing great white sharks, but cage diving seriously limits the possibilities to take ‘fresh’ pictures. When I took this, the water close to the surface was quite milky, making photography very challenging. From out of the “mist”, I saw this great white shark lurking behind a school of fusiliers. I quickly focused on the shark and set a wide aperture to get focus blur on the fish, along with a fast shutter to avoid excessive motion blur”. (Photo by Pekka Tuuri/The Outdoor Photographer of the Year/The Guardian)

Ecuadorian indigenous people celebrate the festival of the moon or Kulla Raymi, in Quito, Ecuador, 21 September 2021. A circle on the ground made up of fruits and inside the Andean symbol of the chacana, multinational geometric flags and a cross that symbolizes the four cardinal points, were the setting in which the festival of the moon, the Kulla, was commemorated this Tuesday. Raymi, on a hill in Quito. It is one of the four most significant festivities of the Andean agroecological calendar, which commemorates the beginning of life and exalts women as the maximum representation of fertility. (Photo by Jose Jacome/EPA/EFE)

Winner, photojournalism. Elephant in the room, by Adam Oswell, Australia Zoo. Visitors watch a young elephant performing underwater. Oswell was disturbed by this scene, and organisations concerned with the welfare of captive elephants say performances like this encourage unnatural behaviour. In Thailand, there are now more elephants in captivity than in the wild. With the Covid pandemic causing tourism to collapse, elephant sanctuaries are becoming overwhelmed with animals that can no longer be looked after by their owners. (Photo by Adam Oswell/Wildlife Photographer of the Year 2021)

An Argentina soccer fan watches the team lose to Saudi Arabia at a World Cup Group C soccer match, played on a large screen in the Palermo neighborhood of Buenos, Aires, Argentina, early Tuesday, November 22, 2022. (Photo by Gustavo Garello/AP Photo)

A sloth peeks out from behind a door on a floating house in the “Lago do Janauari” near Manaus, Brazil, Tuesday, May 20, 2014. Manaus is one of the host cities for the 2014 World Cup in Brazil. (Photo by Felipe Dana/AP Photo)

An Iraqi Muslim woman walks past Christmas decorations for sale in the Shiite holy city of Najaf on December 17, 2015. (Photo by Haidar Hamdani/AFP Photo)

“Theyyam”. Preparation for the Theyyam performance in the surroundings of Kasaragod city. Theyyam is a popular ritual dance form of North Kerala, particularly in Kannur and Kasargod districts. The Theyyam represents a mythological, divine or heroic character. Make up of Theyyams is done by specialist. There are different types of face painting for which primarily and secondary colours are used. Therefore it is essential that the makeup man should have perfect knowledge of primary and secondary colour combinations. Sometimes, it takes several hours to paint each face. Photo location: Kasaragod, India. (Photo and caption by Rafal Ziejewski/National Geographic Photo Contest)