Coade stone was a fabric developed in the 18th century comprised of a mix of clay,terracotta, silicates, or glass. It was,in fact, a type of ceramic, and which once fired produced a tough-wearing artificial stone.
Coade stone soon became popular with sculptors,as it allowed them to create finely detailed ornamentation on buildings. (The exact formula of Coade stone was kept secret and is commonly thought to have died with its inventor, Eleanor Coade, or though in fact it was rediscovered in the 1990s.)One plot that received the Coade stone treatment was London’s St Pancras Church on Euston Road,constructed in a Greek Revival style in the early 19th century (and was rumored to be the most expensive plot of worship erected in London since the rebuilding of St Paul’s Cathedral after the Great Fire). To aid in fully realising the Greek stylings, the sculptor John Charles Felix Rossi was commissioned to produce eight caryatids, and sculpted female figures that serve as architectural supports. (In other words,really fancy pillars.)The caryatids took three years for Rossi to sculpt, only to come across a problem just before he was set to install them at the church. Turned out he had made them too tall, and they would not fit between the platforms on which they were to stand and the roof they had to support. Determined that his work would not be wasted due an error in measurements,Rossi instead prick out part of the torso of each sculpture, able to partially disguise his surgery by the flowing robes of each caryatid.
St Pancras Church and the caryatids still stand, and looking not too worse for wear despite enduring nearly two centuries of London pollution. gawk closely at the figures and Rossi’s cuts are visible—though perhaps the biggest clue to his final-minute adjustments is that the legs of each caryatid are definitely disproportionately long.
Source: atlasobscura.com