Chalcedony in Silicified Microbreccia
Marietta-Tryon Graben
North & South Carolina
By Mike Streeter
January 2012
For about seven years, I have been using geologic maps and other resources to track down the locations of silicified microbreccia with banded chalcedony along a series of faults that extend from just northeast of Tryon, North Carolina to just southwest of Marietta, South Carolina. My original intent was to find mineral specimens, but since I started cutting, polishing and cabbing rocks several years ago, my interest widened to include hunting down lapidary materials. Much of silicified microbreccia I've found has been float (loose rocks eroded from bedrock), but I have found several bedrock outcrops that contain widely disseminated fractured chalcedony and quartz druse.
In February 2005, I tracked down an area in northern Greenville County where silicified fault breccia was plentiful along Gap Creek. I even found spot that appeared to have been frequented by rockhounds, as the creek bank had obviously been disturbed and there were tons of broken rock scattered about. The predominate colors of the banded chalcedony from this location is red, black and yellow in various shades.
In February 2011, I came upon a bedrock location that, for unexplainable reasons, a "little voice in my head" told me to concentrate my digging efforts. Sure enough, I tore into the outcrop and found some nice pieces of banded chalcedony and quartz druse within a highly fractured silicified microbreccia. The pieces were not large, but big enough to make some decent cabochons. In late-December of 2011,, the same little voice returned (or just got louder) beckoning me to return to the spot to dig into it some more and boy am I glad I listened because I hit the proverbial mother lode of banded chalcedony. |
In the summer of 2010, I pieced together vague clues from several sources to pinpoint an obscure and long forgotten chalcedony in silicified microbreccia location near Lake Summit. The chalcedony from this spot is predominately green, yellow and blue.
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Much of silicified microbreccia I've found has been float (loose rocks eroded from bedrock), but I have found several bedrock outcrops that contain widely disseminated fractured chalcedony and quartz druse. In February 2011, I came upon a bedrock location that, for unexplainable reasons, a "little voice in my head" told me to concentrate my digging efforts. Sure enough, I tore into the outcrop and found some nice pieces of banded chalcedony and quartz druse within a highly fractured silicified microbreccia. The pieces were not large, but big enough to make some decent cabochons. In December 2011, the same little voice returned (or just got louder) beckoning me to return to the spot to dig into it some more and boy am I glad I listened because I hit the proverbial mother lode of banded chalcedony. |
(click on each picture to enlarge)
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My years of hunting bedrock sources of banded chalcedony finally paid off with a location that appears to have never before been touched by any other rockhound. Although this "new" rock has a genesis similar to that of Gap Creek Agate and Lake Summit Agate found within the same region, its unique location, colors and textures have prompted me to give it its own name, Carolina Agate. To document my Carolina Agate, I am presenting, as follows, some cut and polished rock pieces, slabs and cabochons of the material I've collected and worked thus far. |
(click on each picture to enlarge)
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Representative Slabs
(click on each picture to enlarge)
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Click here for cabochon pictures on next page . . .
