Coquina is mainly composed of silica sandmany foraminifera shells, cemented by calcium carbonate.Called“foraminifera quartz limestone” in the early days,it was renamed coquina, because some of the rock formations in Penghu did not have foraminifera but some tiny shellfish. The current coquina layer has a porous honeycomb-like shape due to intense weatheringis often mistaken for coral reef limestone. The sites where coquina isdiscovered in Penghu include Hsiaomen Islet, Qimei Township, Niaoyu, Budai Port of Wang-an Township, Paishayuso on. The zoolites of Pleistocene, such as deer bonesantlers, can also be found in the coquina layer of Hsiaomen Islet. As the age of accumulation is relatively young, the bones of these zoolites are still intactnot completely petrified. Coquina is formed in seawater, but why is it exposed on the earth surface? Where do deer bonesantlers come from? It is worth exploring. This specimen was collected from Hsiaomen Islet.