Just a week before Rio de Janeiro hosts South America's first Olympics, city residents expressed mixed feelings about the cost and security of the Games, while holding out hope they will bring joy to a nation facing economic and political crises. The conflicted thoughts mirror a recent survey by the Datafolha polling group showing that half of Brazilians were opposed to holding the Games, while 63 percent think the costs of hosting the event will outweigh benefits. (Photo by Pilar Olivares/Reuters)

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.

Pamukkale, Turkey, is home to these terrace pools, formed by the build-up of carbonate mineral from the warm water flowing from the thermal springs above. (Photo by Image Courtesy of Jennifer Hayes/Getty Images)

Italy's Valentina Greggio during the Women's Speed Skiing at the World Speed Skiing Championship and World Record Attempt in Vars, France, on March 27, 2025. (Photo by Manon Cruz/Reuters)

Japan's computer giant Fujitsu employee displays the world's first personal computer with Intel's RealSense 3D camera “FMV Esprimo” in Tokyo on October 9, 2014. The new desktop PC with 23-inch LCD display can make avatars which mimic the user's look and motion for chatting on the Internet. (Photo by Yoshikazu Tsuno/AFP Photo)

Half-naked girls against speed driving in Nizhny, Novgorod Region, Russia on September 5, 2016. Russian drivers are getting quite an eyeful in a bid to make them slow down thanks to topless women flashing speed limit signs at an accident blackspot. A trial of the road safety campaign demonstrated that it helped lower the speed of traffic near a pedestrian crossing in Severny village. (Photo by YouTube)

A weather vane on a farm building close to the HS2 line on November 24, 2020 in Great Missenden, England. HS2 protesters continue to occupy key infrastructure sites along the proposed HS2 route claiming that the project is “the most carbon-intensive and environmentally destructive project in UK history”. (Photo by Jim Dyson/Getty Images)

A Civil Protection employee dressed as death participates in the campaign “Beware of Monoxide, the Silent Killer”, which seeks to prevent deaths from poisoning with carbon monoxide through the use of heaters to mitigate low temperatures, on an avenue in Ciudad Juarez, Mexico on February 2, 2022. (Photo by Jose Luis Gonzalez/Reuters)