Some [celestite] may be deposited by sea water, but much of the Texas celestite is believed to have been deposited by underground water that seeped through cracks and pores in the limestones and other [sedimentary rocks]. This water picked up and dissolved strontium compounds that were scattered in small amounts through the rocks. Then, it re-deposited the strontium in the rocks as celestite.
In Texas, beds of [celestite] occur in [Permian] rocks in Coke, Fisher, and Nolan counties and in Lower [Cretaceous] rocks in Brown, Comanche, and Mills counties. Celestite geodes and [nodules] are found in Lower Cretaceous [limestone] rocks in Lampasas, Travis, and Williamson counties, and in Permian rocks in Coke, Fisher, Nolan, and Taylor counties.
[Celestite] is one of two minerals (the other mineral is strontianite, strontium carbonate) used as a source of strontium. Strontium compounds give a crimson-red color to a flame, so they are used in fireworks, tracer bullets, and flares. Perhaps you have seen a red flare set out on the highway at night to warn motorists that a truck has stalled. The chances are good that the flare’s red flame was due to a strontium compound. Some of the Texas celestite has been mined, but most of the strontium minerals now used in the United States are imported from England and Mexico.
Cerargyrite. See [Silver Minerals].
Chalcedony. See [Quartz].
Chalcocite. See [Copper Minerals].
Chalcopyrite. See [Copper Minerals].
Chalk. See [Limestone].
Chert ([Flint]). See [Quartz].
Chrysotile. See [Asbestos]; [Serpentine].