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.

Vietnamese artist Hoang Tien Quyet produces curved paper forms using a difficult technique known as wet-folding. This adds an element of sculpture to the work, making Hoàng’s origami animals truly remarkable. Too little water and the paper dries before the folding is done; too much water, and the paper will rip.

The extravagant residence Castello di Sammezzano sits on top of a hill in Tuscany, Northern Italy. Originally it was built in the Moorish style in 1605 for Ximenes d'Aragona and then re-designed between 1853 and 1889. After the war the castello was used as a luxury hotel until closure in the mid to late 1990's. It was abandoned until April 2012 when the FPXA committee was formed, aiming to promote and enhance the castle.

President Barack Obama speaks to the press in the Briefing Room of the White House April 27, 2011 in Washington, DC. US President Barack Obama released a long form version of his birth certificate after extended criticism by those who do not believe he was born in the United States. (Photo by Brendan Smialowski/Getty Images)

A talented portrait photographer has moved on from capturing traditional human subjects – instead photographing a stunning variety of wild animals. Brad Wilson, 51, stands just feet away from the likes of tigers, rhinos, elephants and primates. Each animal is given the same respect and dignity as any human subject, with Brad setting up a full photographic studio, either at or near sanctuaries and zoos across the U.S. The works are the second part of Brad's Affinity series, which the photographer – based in Los Angeles, California, first started working on in 2010. Here: Orangutan. (Photo by Brad Wilson/Caters News)

Sculptures entitled “The Rising Tide” by British sculptor Jason deCaires Taylor are seen beside the River Thames in front of the Houses of Parliament and the London Eye ferris wheel in London, September 3, 2015. The representations of four horses and riders are fully visible at low tide but become immersed underwater twice a day as the Thames rises to reach full tide. The installation will be on display throughout September as part of the annual Totally Thames festival. (Photo by Toby Melville/Reuters)