Verdete is a type of
slate
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. It is the finest grained foliated metamorphic rock. ...
rock found in
Brazil.
Major deposits are found in the state of
Minas Gerais.
The term ''verdete'' is the local name for occurrences of a greenish rock that is high in both
potassium and
iron. The main potassium bearing minerals are
glauconite and
muscovite.
References
Slate
Geology of Brazil
Landforms of Minas Gerais
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