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Onondaga Chert

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  • Onondaga Chert

    Most collections in NW PA and NE Ohio contain, to some degree, Onondaga Chert. Onondaga was brought to this region by the glaciers.

    DeRegnaucourt and Georgiady give the following info and description from "Prehistoric Chert Types of the Midwest"

    GEOLOGICAL STRATIGRAPHY Edgcliff, Nedrow/Clarence, and Moorehouse members of the Onondaga Limestone Formation of the Early to Middle Devonian System.

    OUTCROP LOCATION OR CHERT SOURCE Onondaga is found in escarpment quarries and glacial drift in the Niagara Falls region of western New York and Ontario. The best source is along the Lake Erie shoreline in the province of Ontario extending from Fort Erie westward and also along Lake Erie and the Niagara River on the southern Lake Erie shoreline.

    NATURALLY OCCURING FORM OF CHERT Found as nodular and tabular chert within it's parent limestone matrix. It is often weathered out in small pebbles in the streambeds.

    COLOR The most common color is dark grey. Mottling often occurs with a lighter grey speckled with darker blue-grey including tans and browns. Heat treatment shows little change in coloration and the material becomes less knappable. Munsell colors are N4 thru N7 inclusive, 10YR 6/6, 10YR 6/1, 10 YR 5/1, 5YR 2/1, and 5Y 8/1.

    MINERALS PRESENT Limonite, hematite, dolomite, cryptocrystalline quartz.

    FOSSILS Various fossils have proven to be diagnostic for this chert.

    *Onondaga was used throughout all prehistoric time periods in this area. Below are several examples.



    Attached Files
    Near the PA/Ohio state line

  • #2
    Some nice examples of material and points
    South East Ga. Twin City

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Thank you Johnny

  • #3
    Yep that the stuff alright. Thanks for showing some nice examples. Kim
    Knowledge is about how and where to find more Knowledge. Snyder County Pa.

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Thanks Kim, do you find much Onondaga out your way?

  • #4
    Really nice post Chris, nice that you could put it all together...That’s a honker of a scraper,!..semi glossy patina’s make good lookin points..
    Last edited by Hal Gorges; 12-06-2020, 08:13 PM.
    Floridaboy.

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Thank you Hal, I call that scraper Big Country.

  • #5
    Great post Chris, did you find both pieces of the broken point or did someone break it for you? I really like big country, he may have fleshed out a few wapiti hides..??..some dandy points there also!

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Thanks Carl, found both pieces, as a kid, on separate trips. Big Country is a honker and has some paleo characteristics.

  • #6
    Looks almost like Edwards flint here, good show !
    Lubbock County Tx

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Thank you JJ

  • #7
    Originally posted by paohrocks View Post
    Most collections in NW PA and NE Ohio contain, to some degree, Onondaga Chert. Onondaga was brought to this region by the glaciers.

    DeRegnaucourt and Georgiady give the following info and description from "Prehistoric Chert Types of the Midwest"

    GEOLOGICAL STRATIGRAPHY Edgcliff, Nedrow/Clarence, and Moorehouse members of the Onondaga Limestone Formation of the Early to Middle Devonian System.

    OUTCROP LOCATION OR CHERT SOURCE Onondaga is found in escarpment quarries and glacial drift in the Niagara Falls region of western New York and Ontario. The best source is along the Lake Erie shoreline in the province of Ontario extending from Fort Erie westward and also along Lake Erie and the Niagara River on the southern Lake Erie shoreline.

    NATURALLY OCCURING FORM OF CHERT Found as nodular and tabular chert within it's parent limestone matrix. It is often weathered out in small pebbles in the streambeds.

    COLOR The most common color is dark grey. Mottling often occurs with a lighter grey speckled with darker blue-grey including tans and browns. Heat treatment shows little change in coloration and the material becomes less knappable. Munsell colors are N4 thru N7 inclusive, 10YR 6/6, 10YR 6/1, 10 YR 5/1, 5YR 2/1, and 5Y 8/1.

    MINERALS PRESENT Limonite, hematite, dolomite, cryptocrystalline quartz.

    FOSSILS Various fossils have proven to be diagnostic for this chert.

    *Onondaga was used throughout all prehistoric time periods in this area. Below are several examples.


    Hay Paoh. We find quite a bit actually. But I'm not at all sure that it all comes from N.Y. State
    Knowledge is about how and where to find more Knowledge. Snyder County Pa.

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Agree Kim, most of the Onondaga around here was brought by the glaciers and you can still find a fair amount of it in the river and stream beds.

  • #8
    It was the preferred lithic for Meadowood points in southeastern New England, and likely often arrived here as unfinished Meadowood blades. Had to be imported, could not have arrived by glacial transport.

    Click image for larger version

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    Rhode Island

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Nice relic CMD. Most of the Meadowoods from NW PA are also made from Onondaga.

  • #9
    paohrocks, Thanks for the post and pictures! I used to find Onondaga in New York by the Hudson River but it was always black and, when fresh cracked, had a petroleum smell to it.
    I have heard that heat does not help knapping.

    Comment


    • paohrocks
      paohrocks commented
      Editing a comment
      Thanks bogman, had no idea it smells like petroleum when freshly cracked...

    • Quartzite Keith
      Quartzite Keith commented
      Editing a comment
      I knapped a bit of it many years ago, sent from another knapper on the Canadian side of Niagara Falls. The smell when flaked is distinct and described by most as "fuel oil". Heat treating destroys the rock so it is always worked "raw".

  • #10
    Onondaga chert shows up quite often here in Central Mass.
    Attached Files

    Comment


    • #11
      Wide range of distribution, very nice relic clambellies.
      Near the PA/Ohio state line

      Comment


      • #12
        Here's a close-up of my favorite Onondaga Chert; a couple Meadowood Cache blades, found in far southwestern NY, near the Diver's Lake quarry.
        Last edited by Cmcramer; 12-21-2020, 08:41 AM. Reason: better photo....
        Cayuga County, NY Finger Lakes Region

        Comment


        • paohrocks
          paohrocks commented
          Editing a comment
          Nice examples. appreciate the share.
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