Tuesday, May 22, 2012

Hall's Gap, Kentucky Today

Pictured above is the "productive" side of  the Route 27 road cut in Halls Gap, Kentucky that's known as a classic locality for geodes bearing millerite needles and other sulphides perched upon vibrant pink chalcedony. With low expectations, I decided  to forgo my usual route home to Baltimore from New Orleans (Jazzfest) this May in order to pay the site a visit.

Gleaned from the Internet to form my low expectations were the  following locality descriptions:  cleaned out; filled in; hard to collect; and strictly off-limits. I assumed that most of these descriptions had been posted subsequent to the April, 2003 date where Mindat noted the locality had been reopened. After spending about 90 minutes there, I found myself unable to either confirm or deny any of these contentions.

It was easy enough to locate. Route 27 descends a hill with road cuts on either side immediately north of the Halls Gap Motel.   Where  the road cut ends on the right is a pull-off where you can park. Everything that I collected came from within or the immediate vicinity of that parking area. Hereabouts was enough "geode material," to distract me for a half hour before venturing back to the road cut. Unless one counts the presence of snakes---I observed but one---there were no signs or obstructions to discourage me from collecting.

The cut is through shale. Nowhere in the road cut or amidst the talus beneath it did I observe any other kind of rock. Having since learned that the sulphide-bearing geodes were wedged into the shale in the road cut,  it's possible I didn't look carefully enough. However, if the geodes were there, the work to dislodge them would have entailed more time than my schedule permitted.

So it was back to the parking lot to further inspect what was on the surface there and immediately beneath. Included were numerous geode particles, a few clusters of  quartz crystals to about 5 mm. and quite a bit of  nodular chalcedony, some of it drusy. Exposure to the weather had had dulled any prior vibrancy the chalcedony might have once enjoyed.  I also uncovered a few unbroken geodes ranging in diameter from approximately one to five inches. They were plenty tough to crack. Inside them were chalcedony that curiously appeared as weathered as that which  had lain exposed on the ground,  and plenty  of cleaved calcite along with a few rhombs. Some examples are shown at right.

Once again after the fact, word has reached me of other geode localities in the vicinity of Halls Gap. It has not include word regarding a presence of millerite or other sulphides.
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1 comment:

  1. The Geodes are encased within the shale. You
    have to chisle them out. Back in 1975 when I (Vince Cavanaugh) was a teenager I carved out a couple of Geodes with Millerite in them. I was with another rock collector, Charlie Kelly, on that same day he carved out a large Geode and after opennig it we discovered a large display of Honessite. Yellowish-green color.
    This was simular to the Honessite in the T. Kennedy
    Collection.

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