Dome and plane preform?

[rokdok]

I found this coral piece at the same site as a southern waisted Clovis . On his excellent website Tony Baker a.k.a.Leon discusses the Dome and plane technique for thinning bifaces seen at the L.R.C.C. sites and by Folsom knappers. It appears to me that this is a D&P pre-form which has been domed on one side, and already planed on the other resulting in a plate-like cross section on that side. Is that a nipple left at the base to aid in planing the other side? Maybe the knapper was hesitant to try to plane it because of the irregularities in the stone at that end? What say you, Leon?

[uniface]

My dos centavos : it isn't domed. If it were, there would be in-from-the-sides flakes meeting in a center ridge to guide the planing strike. As is, it looks like a blade from here.

[rokdok]

Go to Tony's website and look at the Dome and Plane section. At the lower end of the page, the Folsom 1 image shows how a naturally flat surface was used opposite the planed surface, similar to this artifact, but this one is much thicker.Apparently a flat surface opposite to the side to be domed is required for a successful planing strike to extend the full length of the piece, as this artifact demonstrates. The next step would be to dome the flat side of this piece and then plane it, according to my interpretation of the process?

[Cluton]

Y'all are too smart for me! I wouldn't have even picked it up!

[leon]

An honest politician is an oxymoron. A politician will never tell you your baby is ugly regardless how ugly the rug rat is. So the question “is this thing a real artifact” is always difficult for me because I am not a politician and I feel an obligation to tell what I believe. (I assume that all understand that an artifact is something that has been humanly modified.) Rokdok, this piece of coral is not an artifact. I say this not because of it morphology, but because of texture of its surfaces. If you were to break this piece into two, the newly created surfaces would be nothing like the current surfaces. The newly created surfaces would be more like the surfaces on a broken piece of glass. I know that time will gradually modify a new surface, but it takes millions of years or more to create the surfaces I see in your images. I have see the surfaces of 400,000 year old handaxes and they look more like recently broken glass that the surfaces of your coral. Sorry, I know this is not what you wanted to hear.

[henry english]

bad drugs , JMHO

henry

[DesertWalker]

Nice translucency, but not an artifact, IMO

[rokdok]

Originally Posted by leon

An honest politician is an oxymoron. A politician will never tell you your baby is ugly regardless how ugly the rug rat is. So the question “is this thing a real artifact” is always difficult for me because I am not a politician and I feel an obligation to tell what I believe. (I assume that all understand that an artifact is something that has been humanly modified.) Rokdok, this piece of coral is not an artifact. I say this not because of it morphology, but because of texture of its surfaces. If you were to break this piece into two, the newly created surfaces would be nothing like the current surfaces. The newly created surfaces would be more like the surfaces on a broken piece of glass. I know that time will gradually modify a new surface, but it takes millions of years or more to create the surfaces I see in your images. I have see the surfaces of 400,000 year old handaxes and they look more like recently broken glass that the surfaces of your coral. Sorry, I know this is not what you wanted to hear.

An interesting observation. I took this to a geologist at the local university and he assured me that this agatized coral with a hardness on Mohs scale of 7 is too hard for natural forces to fracture in this manner. We discussed the geology of this area, and south Georgia was a warm shallow sea for 35 million years and was formed by sedimentary processes primarily from the erosion of the Appalachians.There are no Hills for rocks to roll down and fracture, and riverine forces are not able to generate forces able to fracture agate. This coral occurs in nodules ranging from fist size to several feet in length. I have enclosed pix of the natural cortical surfaces.An interesting dilemma,asi am confident in your experience, as well as the geologist who is well experienced.I took a hammer and broke the cortex in the last picture to expose the agatized center.

[rokdok]

A limace from the same site.

[Cluton]

Still not an artifact in my mind! Sorry just not seein anything there at all!