Cay Sandstone or “Beach Rock” (18) Published February 17, 2013 at 2240 × 1700 in Cay Sandstone or “Beach Rock” Cay Sandstone or “Beach Rock” (18) – Small Tropical Rock Crab (Grapsus sp.) in a tide pool in recently formed Cay Sandstone or “Beach Rock” on Normanby Island, Queensland, Australia, part of the Frankland Islands group. P1180648aBlog18 About these ads