A reveller catches beer thrown from a balcony during the opening day or “Chupinazo” of the San Fermin Running of the Bulls fiesta on July 6, 2017 in Pamplona, Spain. The annual Fiesta de San Fermin, made famous by the 1926 novel of US writer Ernest Hemmingway entitled “The Sun Also Rises”, involves the daily running of the bulls through the historic heart of Pamplona to the bull ring. (Photo by Pablo Blazquez Dominguez/Getty Images)

Girls of University of Cincinnati Stage Grecian Games on April 29, 1921. Garbed in costumes of ancient Greece, fair students of the University of Cincinnati, Ohio arranged a set of Grecian Games for the benefit of the University athletic fund. All of the girl students of the University, who take a great interest in outdoor games and athletics, took part in the games. The fund was greatly increased through the staging of the unique attraction and the girls purpose to give a return engagement. The accompanying photographs show the girl contestants in their Grecian costumes. Photo shows the start of the 100 yard dash. (Photo by Bettmann Archive/Getty Images)

Woman and man playing domination games in bed. (Photo by NDAB Creativity/Rex Features/Shutterstock)

Beautiful woman and man playing domination games in bed. (Photo by nd3000/Getty Images)

Opossums on their mothers back at a game reserve in Central Minnesota, USA, on September 2, 2013. (Photo by Caters News Agency)

There is an endless bounty of eye-catching gemstones throughout the world and this spectacular boulder opal is one unique beauty that looks like a shimmering crystal encased in a tree fossil. Its opalescent sheen seeps through the cracks of the seemingly wooden rings in lustrous hues of emerald green and aqua blue. Like something out of a fairy tale, the triangular piece radiates through an organic pattern mimicking the growth rings of tree.

A firefighter battling the King Fire watches as a backfire burns along Highway 50 in Fresh Pond, California September 16, 2014. The fire led officials to call on about 400 people to evacuate from areas threatened by the blaze, Cal Fire spokeswoman Alyssa Smith said. It has charred more than 11,500 acres (4,654 hectares) and was 5 percent contained on Tuesday. (Photo by Noah Berger/Reuters)

Members of the Edo Firemanship Preservation Association balance on top of bamboo ladders during a demonstration at the New Year's fire review held by the Tokyo Fire Department in Tokyo, Japan, 06 January 2016. Some 2,800 firefighters perform various emergency rescue and firefighting demonstrations in an effort to promote the prevention of fire and disaster in the annual event. (Photo by Kiyoshi Ota/EPA)