Heavily Weathered or Re-formed Older Agates

What do we mean by uniquely diverse agate formations from the “Carver” agate find?

There are two other agate formations which are commonly seen on the “Carver.”

The first, shown in photo 191, is a rather typical shape, which suggests that it was formed in a manner consistent with a vein agate.  The coloration range is moderately broad, although not nearly as broad as the color variation contained in the agate nodules found throughout  the “Carver.”  Another characteristic of this particular material is that it generally has an exterior rind of a whitish color (probably quartz) concealing almost entirely the interior agate material.  These are only found eroded out of their original matrix and accordingly appear to be of an earlier formation than many of the agate nodules which are still found in some instances in matrix.  What could be described as an old vein agate may have been re-formed subsequent to its initial formation, perhaps while embedded in eroded material.  There is some suggestion in these vein agates of subsequent re-agatization .    Frankly, the formation of these agates is quite mysterious to this writer.

Rocks #191
Photo 191

The second type of rind agate, shown in the photos below, are more beautiful and varied in color, with a finer agate pattern than most of the agates found on the “Carver.”  These have relatively little large or obvious sagenitic material.  Their shape  is blocky and irregular, suggestive that they represent broken pieces of larger agate material.  I believe that the white rind which usually covers all sides of the irregularly shaped agates is indicative of some sort of reformation of the broken materials after re-bedding.  The interior agate material is incredibly varied both in color and pattern, as you can see.   The geological age and origin of these materials is not at all clear to this writer, except to say that they do not have the appearance of an origination as a nodule or geode as commonly found throughout  the “Carver.”

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