Small Greenstone Celt Peckalong/Virginia

dixieshedhunter
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dixieshedhunter
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Joined: December 10th, 2017, 5:23 pm

September 15th, 2018, 1:50 am #1

This celt project, as yet unhafted, started in mid-July. The cobble was procured from the Pedlar River in Amherst County, Virginia. Greenstone outcrops in Long, Brown and Pompey Mountain represent the southern extent remnant of the Catoctin lava flows. These basalts were extruded some 600 million years ago in a huge volcanic event that accompanied the rifting of the ancient continent of Rodinia and the formation of the Iapetus ocean. Although this formation started out as simple basalt, the rock has been thermally altered by metamorphism and fractured by severe tectonic activity, deformed and foliated, buried deep under rising mountains, re-exposed by erosion and weathered into everything from soft shale gravel to glassy stream cobbles the size of a human leg. Catoctin metabasalt has had it's constituent minerals largely replaced and consists of amphibole(actinolite), feldspar, chlorite, epidote, copper, magnetite and others. The basalts in the southern  Amherst area tend decidedly to a schistose and layery character. There are solid and unfoliated sections within the formation here, but most of the basalt in the Long Mtn exposures is rough. This material was used in an extensive local flaked axe industry well into woodland times, and flaked axes of this foliated material are commonly found in the area..

When gathering these materials with peck and polish in mind, I have learned to avoid the outcrop and surface material, and rather to follow the basins downward and to search the streams where they gain in flow and bedload cobbles become smaller. The Pedlar here is of high gradient and a largely dioritic bedload. Time and sometimes violent transport have beaten the hardest material from the soft, and left  remnant cobbles of the Catoctin metabasalt here and there. They tend to take on a dark cortical staining which effectively hides them among the diorite and schist cobble beds. The high gradient ensures just a few real cobble piles. But with effort a few workable pieces of basalt can be procured.

Regretfully I didn't get a pic of the raw cobble-but will follow the process along with what pictures I have. Persons undertaking tools of this technology are well advised to be patient and to go easy on yourself. Unlike in knapping, completion is usually measured in weeks. Pecking can lead to fatigue at best and trauma at worst.


Used my jasper pecking stone to take flakes from the edge with downward blows that glance somewhat to avoid shock.




The cortex, over a vexing ridge hump that needed to be dispensed with in several stages of battering and abrasion.





Here I have started to batter the ridge/hump.




First pass against the ridge/hump reveals the material under the rotten cortex.




That round of battering was ground over and battering commenced again. This isn't a faster reduction strategy but ground surfaces reveal contour more accurately.






Second battering has started to remove the excess dorsal convexity.

Last edited by dixieshedhunter on September 15th, 2018, 12:34 pm, edited 2 times in total.
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dixieshedhunter
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dixieshedhunter
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September 15th, 2018, 1:56 am #2




Grinding aggressively in a sand slurry on my steps.




This second grinding reveals several layers in the core: cortex, a secondary layer of sub-cortical staining and pure unweathered catoctin greenstone underneath all. Judging from the effort of battering, the second stained layer is as hard as the unweathered core. 




Most of the convexity has been dealt with, as the two face sides will become more, but never perfectly equalized as the edges are battered toward centerline.




Here the grinding has revealed an intrusive, healed crack. The intrusion might be quartz, epidote, or other materials. these cracks needn't be a worry as they are often as strong as the parent material. 




Testing for flaws is a constant. Here I have soaked the celt core in warm water and allowed the water to evaporate slowly. Structural cracks will often retain water for an extra instant and reveal themselves as danger. This healed fracture shows no retention at all. 




Now back to battering the other face. Both flake ridges are taken down and an attempt is made to bring the face from concavity, to flatness, to convexity.




One edge has been battered to roundness. The grind of the humpy face contrasts with the battered edge and  shows the inherent volcanic beauty of the material. Tantalization! 

Last edited by dixieshedhunter on September 15th, 2018, 1:07 pm, edited 3 times in total.
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dixieshedhunter
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dixieshedhunter
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September 15th, 2018, 2:05 am #3


Using the pen to establish battering priorities.




Looking at the other edge to be rounded over.
 



And establishing a negotiable margin to be pecked toward.




Negotiations well under way. 



Prosecution is battering the witness! Here both edges are now tentatively rounded, and the flatter face still becoming more convex via pecking. Face pecking requires some finesse to avoid risk of fracture. It helps to batter in a gentle arc toward the greatest mass. 



Putting a mild curve across the long axis of the tool by lowering the poll face on the humpy side.  Not actually required, more a front/back agreement issue. Many artifacts retain much of the character of the parent pieces of stone. Thus opening the discussion to the incremental gradients of effort and fineness of manufacture, from purely expedient tools with polished edges, through grave-quality perfection pieces that are shaped with great precision and exhibit polish in their entirety. . 




Here we are ground and dry, and approaching final bit establishment.




Most of this ghostly cortex will remain as an artifact of the original source form. Common in aboriginal examples. 




Polished edge, showing how the single bit face has been ground in.

Last edited by dixieshedhunter on September 15th, 2018, 1:14 pm, edited 2 times in total.
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dixieshedhunter
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September 15th, 2018, 2:10 am #4



Final grind is over!




Our bit is ready for whetting too. Angles are arced toward the bit-never flat.




To wit:




Toweled off.








My three summer celts. Outer two are catoctin metabasalt, the center celt is from Blue Ridge dolerite, and intrusive basalt that has cooled slower in the ground and exhibits less fineness of grain. 



That's whole a fistful of work, son. Getcha some! 

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Forager
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Forager
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September 15th, 2018, 3:10 am #5

Thank you Pete for this outstanding documentation of geology and your beautifully detailed process of manufacture.  I will be among the many who will be following your ongoing efforts.  

Plenty of excellent crafting method underway here.
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VirginiaKnapper
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September 15th, 2018, 3:32 am #6

Incredible work and process Pete! I really love your work with greenstone celts and axes. How many hours of pecking/ hours concering total process including grinding take? In addition, did you attempt to make an average of how many pecks it took?

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"It's about what you learn, not what you make" - Erret Callahan
"Nothing like busting out a Savannah River out of some gnarly shit." - Robert Godshall, 1st annual ThunderRidge knap in.
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dixieshedhunter
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dixieshedhunter
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September 15th, 2018, 3:41 am #7

I'll put this one in the 15 hour range. Grinding only four of that. 

PD
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Michael Bootz
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Michael Bootz
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September 15th, 2018, 10:01 am #8

Another super-cool project. Thanks so much for posting this!
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Hummingbird Point
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Hummingbird Point
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September 16th, 2018, 4:02 pm #9

Awesome.  Any collector or archaeologist trying to understand this technology needs to read this!
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