A boy walks with toy guns as people ride an APC during a military show at the Finnish Gulf coast in St.Petersburg, Russia, Saturday, September 5, 2015. (Photo by Dmitry Lovetsky/AP Photo)

Wednesday March 8 marks International Women's Day, with festivals, concerts and exhibitions among the numerous events planned around the world to celebrate the achievements of women in society. The annual event has been held since the early 1900s and traditionally promotes a different theme each year, with this year's edition calling on people to #BeBoldForChange and push for a more gender-inclusive working world. Reuters photographers have been speaking with women in a range of professions around the world about their experiences of gender inequality. Here: Yolaina Chavez Talavera, 31, a firefighter, poses for a photograph in front of a truck at a fire station in Managua, Nicaragua, February 22, 2017. (Photo by Oswaldo Rivas/Reuters)

Russia's Darya Klishina prepares for the women's long jump qualification during the athletics competitions of the 2016 Summer Olympics at the Olympic stadium in Rio de Janeiro, Brazil, Tuesday, August 16, 2016. She might be feeling the pressure of being all alone, but Darya Klishina could yet still win Russia's only athletics medal at the Rio 2016 Games. (Photo by Matt Dunham/AP Photo)

Transgender Kendra Ferrari, 21, performs during Miss Night Queen beauty contest in Guatemala City, Friday, June 15, 2012. Ferrari won the pageant and will represent the transgender community for one year. (Photo by Rodrigo Abd/AP Photo)

The lightest material ever made has been produced by a team of scientists in China, a Chinese university announced.

“A Double Eagle is a gold coin of the United States with a denomination of $20. (Its gold content of 0.9675 troy oz was worth $20 at the then official price of $20.67/oz). The coins are made from a 90% gold (0.900 fine = 21.6 kt) and 10% copper alloy”. – Wikipedia

Photo: A “Double Eagle” gold twenty dollar coin is displayed above a catalogue picture showing the reverse side of the coin at Goldsmith's Hall on March 2, 2012 in London, England. Nearly half a million of these coins were originally minted in the midst of the Great Depression in the US. Only 13 are known today after the rest were melted down before they ever left the US Mint, sacrificed as part of a strategy to stabalise the American economy. In 2002 a Double Eagle sold at auction for $7.6 million. (Photo by Peter Macdiarmid/Getty Images)

A groundskeeper uses a bamboo broom at Kasumigaike Pond at Kenrokuen Garden in Kanazawa, Japan on January 12, 2016. The japanese garden, located next to Kanazawa Castle, encompasses over 28 acres in downtown Kanazawa. With two ponds, rolling hills with streams and bridges, is considered a strolling-style landscape garden. It's regarded as one of the top three most beautiful gardens in Japan. (Photo by Linda Davidson/The Washington Post)

People wait on a taxi line near Madison Square Garden, Wednesday, September 23, 2015, as a 225-foot-tall hand-painted billboard of Pope Francis stands out at Eighth Avenue in New York. The billboard, designed by Israel Ochoa of DeSales Media, including a photo by photographer Giulio Napolitano, marks the arrival of the pope Thursday. (Photo by Craig Ruttle/AP Photo)