If we were to burn NH4Cr2O7 with HgSCN in the Dark Ages in Europe and show it to anyone, it is us who would be burning next on a fiery cross of Inquisition. And it’s no wonder, since this experiment produces a truly marvelous result. At first, as you ignite the mixture of NH4Cr2O7 and HgSCN, all you can see is that it is slowly burning with a reddish flame. After a while, however, a crater is formed in the middle of the burning pile, and then, suddenly, tentacle-like appendages start sprouting from the burning mixture. And you can almost hear the scream of the mad occultist – “Come forth, Kraken! Come forth!” But of course, this is simply a chemical reaction that is called the "Pharoah's Serpent". It was also often sold in firework stores until people realized that it was toxic.

After the success of their Superman series in 2013, the Canadian Mint debuted a new set of coins honouring the Man of Steel at this year's Fan Expo in Toronto. The collection is made up of three silver coins worth $10, $15 and $20, and a gold coin worth $100. Photo: Close-up of the $10 silver coin in the new Superman series from the Royal Canadian Mint. (Photo by The Canadian Press)

Student, Shoukria positions a stone for cutting at the Turquoise Mountain Gem cutting class on May 18, 2011, in Kabul, Afghanistan. The mineral resources of Afghanistan are relatively unexplored even with Afghanistan's mineral wealth of coal, copper, gold and iron ore, with precious and semiprecious stones, including high-quality emerald, lapis lazuli, red garnet and ruby. Given the country's remote and rugged terrain, on-going instability plus an inadequate infrastructure and transportation means that mining is still difficult. While many are trying to bring positive changes, Afghanistan's mining industry uses unregulated, primitive methods and outdated equipment. (Photo by Paula Bronstein/Getty Images)

Giffords Circus’s show is touring the UK. Established in 2000, Giffords Circus is a small circus company that delivers circus / theatre fusion to the villages and market towns of the south west. It combines dance, comedy, horses and live music in a two-hour show, located on village greens in a small white tent surrounded by handmade burgundy and gold showman’s wagons. Photographer Tom Pilston goes behind the scenes to meet the performers. Here: The incredible, gravity-defying Konjowoch Troupe. (Photo by Tom Pilston/The Guardian)

Looking for an escape from the daily realities of crisis-ridden Venezuela, Carmen Gomez finds solace receiving visitors on the roof of her Caracas apartment building every morning: groups of blue and gold macaws that arrive at daybreak. Here: A macaw lands in Carmen Borges' hand while she stays at a rooftop of a building in Caracas, Venezuela, June 12, 2019. (Photo by Manaure Quintero/Reuters)

The underbelly of fetish parties has been exposed in photographs captured by Belgian photographer MagLau. The photographer dedicated three years to capturing the obsession with leather and chains, visiting fetish parties through Europe and Japan. The photographer told: “I just took pictures, always finding some beauty in the dark side”. He said that most people were happy to be photographed for the project, with the images included in a new book Fetish Ballad. Aiming to capture the candid moments, he said he never judged but instead wanted to simply observe and understand. Here: Picture from Fetish Ballad book. (Photo by MagLau/Laurent Muschel)

“Friedrich Christian Anton “Fritz” Lang (December 5, 1890 – August 2, 1976) was an Austrian-American filmmaker, screenwriter, and occasional film producer and actor. One of the best known émigrés from Germany's school of Expressionism, he was dubbed the “Master of Darkness” by the British Film Institute. His most famous films are the groundbreaking «Metropolis» (the world's most expensive silent film at the time of its release) and «M», made before he moved to the United States, his iconic precursor to the film noir genre”. – Wikipedia

Photo: Director Fritz Lang (right) and crew members inspect the robot from the film “Metropolis”, which is made to resemble the saintly Maria. (Photo by Hulton Archive/Getty Images). Circa 1926

A “Star Wars” superfan has brought the universe to his backyard. Amateur photographer Zahir Batin, from Selangor in Malaysia, added stormtroopers, X-wings and other famous sights to his native Tanjong Karang rice fields. The Malaysian snapper decided to combine his love for his hometown with his passion for the out-of-this-world space opera and, in particular, the toys. The amazing shots show TIE fighters on fire flying overhead and AT-AT walking tanks towering over tiny children, as well as Dark Side forces marching through the countryside. Here: a Nubian Royal Starship hovers over the Malaysian rice fields. (Photo by Zahir Batin/Mercury Press)