Agate
is identical with quartz in composition and physical properties.
Composed of silicon dioxide (SiO2), it has a hardness of
7, a glassy luster, a conchoidal fracture, and a specific
gravity of 2.60. Most agates occur in cavities of eruptive
rocks or ancient lavas. These agates have a banded structure,
successive layers being approximately parallel to the sides
of the cavity. During crystallization, the colored bands
are not disturbed. Varieties of agate are characterized by
peculiarities in the shape and color of the bands. Here is
a list of agate:
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Chalcedony with
concentric banding is also known as agate. |
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Dendritic
Agate has beautiful fern like patterns on
them formed due to the presence of manganese and
iron ions. |
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Moss
Agate is a form of agate which includes minerals
of a green colour embedded in the chalcedony, forming
filaments and other patterns suggestive of moss. |
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