Stanley was a particularly enlightened and progressive clergyman who questioned the literal truth of the creation in the Book of Genesis. It is interesting to note that he enjoyed a lifelong friendship with T. H. Huxley, a follower of Darwin.

Mary Grant was one of the most eminent female sculptors of nineteenth-century Britain, with numerous commissions from the rich and famous.

Born in Kilgraston, Perthshire, Scotland, her maternal grandfather was the 7th Earl of Elgin, her aunt was Mary Anne Grant, a portrait and landscape painter, and her uncle was Sir Francis Grant, a highly successful portrait painter and president of the Royal Academy.

She began sculpting in the 1850s and studied in Florence under Odoardo Fantacchiotti in the early 1860s and with John Gibson in Rome. Grant then went to Paris and studied with Michel Mercier. She established a studio in London in the late 1860s and worked under the direction of John Foley in 1868–1869.

Blue John is a semi-precious mineral, a form of fluorite with bands of a purple-blue or yellowish colour. In the UK it is found only at Blue John Cavern and Treak Cliff Cavern at Castleton in Derbyshire. During the nineteenth century, it was mined for its ornamental value, and mining continues on a small scale.