American artists have drawn criticism after making stunning, intricate sculptures by pouring hot liquid aluminium into anthills.

A model showcases designs on the catwalk by Manning Cartell during A Review of Australian Fashion Week show as part of Mercedes Benz Fashion Festival Sydney 2011 at Sydney Town Hall on August 27, 2011 in Sydney, Australia. (Photo by Don Arnold/Getty Images)

A young man with the date 25 painted on his face, gives the victory sign in Tahir Square ahead of the first anniversary of the revolution on January 24, 2012 in Cairo, Egypt. (Photo by Jeff J Mitchell/Getty Images)

Police officers take cover as they clash with protesters after an officer shot and killed a black man in Brooklyn Center, Minneapolis, Minnesota on April 11,2021. Protests broke out April 11, 2021 night after US police fatally shot a young Black man in a suburb of Minneapolis – where a former police officer is currently on trial for the murder of George Floyd. Hundreds of people gathered outside the police station in Brooklyn Center, northwest of Minneapolis. Police fired teargas and flash bangs at the demonstrators, according to an AFP videojournalist at the scene. (Photo by Kerem Yucel/AFP Photo)

Sukaregang in Garut district, West Java, has long been a bustling center for Indonesia's leather trade, with some shops producing and selling various goods – including bags, shoes and jackets – since the 1940s. The industrial area is also a major supplier for high-end brands from across the globe, catering to the fashion, auto and motor-sports industry. Here: a man walks across a vat of water used to wash the hide. (Photo by Rezza Estily/JG Photo)

Alfred Yetta (L) and Kay Manning pose for a photo in front of a cardboard cut-out of Pope Francis, during an event organised by Christa Scalies, the co-creator of the Pop-Up Pope, in Fado Irish Pub & Restaurant in Philadelphia, Pennsylvania, September 16, 2015. (Photo by Mark Makela/Reuters)

A woman smokes a cigarette next to man wearing a mask during lunch hour at the central business district in Singapore September 29, 2015. The 3-hour haze Pollutant Standards Index (PSI) reached a high of 173 at 8am on Tuesday, according to the National Environment Agency. Slash-and-burn agriculture in neighboring Indonesia has blanketed Singapore in a choking haze for weeks. (Photo by Edgar Su/Reuters)

A man dressed as a devil poses next to a grafitti of late rebel hero Ernesto "Che" Guevara in the indigenous community of Monimbo in Masaya, Nicaragua, October 16, 2015. People prepare to participate in the popular annual festival called "The Aguizotes" held on the last Friday of October, where residents dress up as characters from legends and folklore mythology of Nicaragua. (Photo by Oswaldo Rivas/Reuters)