In 1952 Clark provided the scenario for and edited the Twayne Science Fiction Triplet "The Petrified Planet", which has been described as "the first 'shared world' anthology". The scenario postulated a star system inhabited by silicon-based life forms, and was used as the basis for the three novellas by Pratt, H. Beam Piper and Judith Merril forming the body of the work. An excerpt from Clark's introduction ("The Silicone World") was reissued in the December, 1952 issue of "Startling Stories", and the whole was reprinted in the 1983 Ace edition of Piper's contribution to the book, "Uller Uprising". However, the "Startling Stories" excerpt has also been credited to Pratt, who supposedly utilized Clark's name as a pseudonym.