You can walk the walk, but can you talk the talk?

[JackCrafty]

Here's the definition of "Prismatic Blade" from wikipedia.  See if you can get through this and understand EVERY WORD.

In archaeology, a prismatic blade is a long, narrow, specialized lithic flake with parallel margins. Prismatic blades are removed from polyhedral blade cores through pressure reduction. This process results in a very standardized finished tool and waste assemblage. While the prismatic blade industry is most often associated with obsidian (especially in Pre-Columbian Mesoamerica), it is not limited to that material; chert, flint, and chalcedony blades are not uncommon.

Morphology
Prismatic blades are often trapezoidal in cross section (see image), but very close in appearance to an isosceles trapezoid. Triangular blades (in cross-section) are also common. The ventral surface of the prismatic blade is very smooth, sometimes bearing slight rippling reflecting the direction of applied force and a very small bulb of applied force (indicative of pressure reduction). Flake scars are absent on the ventral surface of these blades, though eraillure flakes are sometimes present on the bulb . The dorsal surface, on the other hand, exhibits scar ridges running parallel to the long axis of the blade. These facets are created by the previous removal of blades from the core. The proximal end contains the blade's striking platform and its bulb of applied force, while the distal end will consist of a snap break, a feather termination, or a stepped termination.

Production
Obsidian prismatic blade production was ubiquitous in Mesoamerica, and these tools can be found at a large majority of Mesoamerican archaeological sites from the Preclassic period on until the arrival of the Spanish in the early 16th century. Ethnohistoric sources recount the process of prismatic blade production. Fray Motolinia, a Spanish observer, recorded:

    It is in this manner: First they get out a knife stone (obsidian core) which is black like jet and 20 cm or slightly less in length, and they make it cylindrical and as thick as the calf of the leg, and they place the stone between the feet, and with a stick apply force to the edges of the stone, and at every push they give a little knife springs off with its edges like those of a razor.

The production of prismatic blades creates not only a very standardized final product, but also a standardized waste assemblage. The analysis of obsidian debitage can reveal whether or not prismatic blade production occurred at a site and, if it had, what stages of production the process included. In other words, the types of manufacturing waste present (e.g., rejuvenation flakes and/or blades, platform rejuvenation flakes, etc.) at a site can inform archaeologists about the stage in which blades were being produced.


This type of wording is typical of archaeological texts.  It's no wonder people don't read those things.....

Oh yeah, and it's not entirely correct either. 

[TRACY]

It's got to be true because its on the Internet Mr. Jackcrafty!


Tracy

[iowabow]

Scott and I watched a guy do this at the Devel's hole knapin.

[JeremiahVires]

In archaeology, a prismatic blade is a long, narrow, specialized lithic flake with parallel margins. Prismatic blades are removed from polyhedral blade cores through pressure reduction. This process results in a very standardized finished tool and waste assemblage. While the prismatic blade industry is most often associated with obsidian (especially in Pre-Columbian Mesoamerica), it is not limited to that material; chert, flint, and chalcedony blades are not uncommon.

Pretty much what they are saying is that a prismatic blade is a long, narrow and symmetrical blade.  They are removed from blades that have many side through pressure flaking.  This results in a good looking tool with little waste, or waste that can be reused for other purposes.  Usually the prismatic blade is made with obsidian, but can be made, and are often made, of chert, flint and almost any knappable material availiable.

[JackCrafty]

Yes, internet wisdom cannot be questioned...

Hmmm...  I don't think I've heard of the Devil' hole knap-in.

Jeremiah, yes, but do you understand the terms like "assemblage" and "industry" and the differences between them?

[JeremiahVires]

Industry is the manufacture, and assemblage is the the process of actually making them, correct?

[JEB]

YUP, that was clear as mud!!!

[JeremiahVires]

 

[JackCrafty]

Nice try.   

Industry = technology + methods.

Assemblage = finished objects + waste.

[Stringman]

Yep, I remember that guy, John. Can't remember his name but he was an old guy and he was really good at poppin those blades off. They were surgery sharp and usually about 3" long but rarely over 1/4" wide. Very impressive to see the process.

Patrick, Devils hole knappin is held in fairview heights, IL about this time every year. Some very talented knappers were there last year demonstrating their skills with several vendors selling rocks.

[JackCrafty]

Dang, if Illinois wasn't such a drive for me I'd be there!