Cay Sandstone or “Beach Rock” (6) Published February 17, 2013 at 2240 × 1700 in Cay Sandstone or “Beach Rock” Cay Sandstone or “Beach Rock” (6) – Broken slab of coral fragments and shells cemented together in Cay Sandstone or “Beach Rock” on Normanby Island, one of the Frankland Islands, Queensland, Australia. P1180606aBlog6 About these ads