Giant Crystals... Youngblood Library Minerals
Description: These five, giant clear-to-colorless and translucent selenite crystals range in length from approximately 3.25 to 4.25 feet (122 to 160 centimeters), provide a spectacular impression of "Star Wars light sabers".
They were initially thought to have been removed from a 100 meter length room in the "Cave of Swords" section of the Gibralter Silver Mine near Nacia in the State of Chihuahua, Mexico. It is now believed that they were recovered from one of the cave rooms of the Caverna de Santo Domingo, located near Santa Eulalia, also in the State of Chihuahua, Mexico. Both of these mines are located in Early Cretaceous limestone formation from which sulfide minerals are mined. While the limestone is estimated to be 97 million years old1, the age of the crystals cannot be determined, since crystals in other locations have been observed growing in historical times.
Selenite crystals are generally created as water migrates through sulfide ore-enriched limestones, such as these in the Early Cretaceous, thereby dissolving the sulfide ores and creating sulfuric acid. As water reacts with limestone, it then becomes saturated with sulfate and calcium, resulting in the creation of gypsum-laden water drops which then formed these large clear to colorless selenite (CaSO4*2H2O) crystals.
1 Limestone cave estimated by traditional Uniformitarian concepts (with gradual, uniform changes over great periods of time, commonly believed to be similar to rates of change observed today.
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