Agatized Coral
State Stone
Identification: Agate, or chalcedony, is a variety of cryptocrystalline quartz (SiO2). It is found in a variety of colors, typically gray, brown, black, white, and sometimes red. Fossil corals and mollusks may be replaced with agate deposited by silica-rich ground water percolating through limestone. In 1979 the Florida Legislature designated agatized coral as the Florida State Stone. It is described in the statute as “a chalcedony pseudomorph after coral, appearing as limestone geodes lined with botryoidal agate or quartz crystals and drusy quartz fingers, indigenous to Florida.”

Occurrence: Much of Florida’s agate, including the Tampa Bay agatized coral, formed in the Oligocene-Miocene Hawthorn Group sediments (see time scale). Once abundant at Ballast Point in Tampa, it is occasionally dredged up in the Tampa and Clearwater areas. It also occurs in limestones along the Econfina, Withlachoochee and Suwannee Rivers. An Oligocene variety is sometimes found in Suwannee Limestone quarries north of Tampa.

Use: Agatized coral, particularly in the form of large geodes, is prized by gem and mineral collectors.

This was copied from the State of Florida website: Geological Survey - Geology Topics / Florida Department of Environmental Protection. To review Floridas Rocks & Minerals click here.

Moonstone State Gem
States astronauts Neil Armstrong and Edwin (“Buzz”) Aldrin landed on the moon on July 20, 1969, aboard the Apollo 11 spacecraft. Since this and all other astronaut-controlled spaceflights had been launched from the Kennedy Space Center in Brevard County, the Florida Legislature sought to memorialize this “giant step” for humankind. In 1970, lawmakers adopted the moonstone as the official state gem.