In petrology, the term "chert" refers generally to all chemically precipitated sedimentary rocks composed primarily of
The … See more

The cryptocrystalline nature of chert, combined with its above average ability to resist weathering, recrystallization and metamorphism has made it an ideal rock for preservation of early life forms.
For example: … See more

Chert is of only modest economic importance today as a source of silica (quartz sand being much more important.) However, chert deposits may be associated with valuable deposits of iron, uranium, manganese… See more

There are numerous varieties of chert, classified based on their visible, microscopic and physical characteristics. Examples are:
• Flint is a compact microcrystalline quartz. It was origina… See more

• Petrology – Branch of geology that studies the formation, composition, distribution and structure of rocks
• Archaeology – Study of human activity based on materials that people have left behind. … See more

• Photo & note re: Fig Tree Formation
• Microphotographs of Fig Tree fossils
• Schopf, J.W. (1999) Cradle of Life: The Discovery of Earth's Earliest Fossils, Princeton University Press, 336 p. ISBN 0-691-00230-4… See more