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This specimen is an example of a metallic mineral that formed in a sedimentary environment.
Sedimentary: General Collection
Mechanical and chemical weathering of Earth’s rocky crust supply mineral materials to new sites of deposition. While some minerals formed in the site of deposition are mechanical accumulations, or placer deposits, others may be chemical precipitates.
Even bacterial activity may play an important role n the precipitation of sulfur- and iron-bearing minerals. Whether or not biochemical processes are responsible for the precipitation of galena or hematite, for example, has been a subject of long-standing debate and remains an unresolved problem.