Lewis & Short

2. Marpessus (Marpēsus), i, m., = Μάρπησσος, a mountain in the island of Paros, in which lay the quarries of Parian marble, Serv. Verg. A. 6, 471.
Hence, Marpessĭus (Marpēsĭus), a, um, adj., of or belonging to Marpessus in Paros, Marpessian; and transf., Parian: Marpessia cautes, i. e. Parian, Verg. A. 6, 471; and referring to the above passage, Marpessia rupes, Arn. 2, 60.