„The Black Opal: A Romance of Thrilling Adventure” was written by Fenton Ash and was first published in 1906. It is a lost race adventure novel set in a medieval kingdom in the Sargasso Sea. Fenton Ash is the first and main pseudonym of UK civil engineer and author Francis Henry Atkins (1847-1927) who was a writer of „pulp fiction”, in particular science fiction aimed at younger readers. He was involved in a scandal at the turn of the century and sentenced to nine months imprisonment for obtaining money by deception. After leaving prison he dropped the name Frank Aubrey and – in his early 60s, following a three-year hiatus – began writing as Fenton Ash.