Natural clay questions

Discussion in 'Other Skills' started by Willem208, Mar 7, 2019.

  1. Willem208

    Willem208 Tracker

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    I have finally succeeded in purifying clay that I dug up. I have been using the clay for bullets for my sling. I want to try primitive pottery soon. First question is, what do you use as temper to stop the clay from cracking, shrinking and losing weight? I made a ball with the unpurified clay with about 25% sand (builders or sandpit sand whatever you call it) mixed in. It has dried well with no cracking, little shrinking and very liitle weight loss. Is sand good or is there a better choice?Second I am just wondering if anyone has got ideas, websites or resources that can benefit me for trying primitive pottery. For reference, I am in South Africa and my clay is red. I am still not sure if it is great clay but I will soon find out after more experiments! Many thanks.
     
  2. MrFixIt

    MrFixIt Old Jarhead LB#42 Supporter Bushcraft Friend Bushclass I

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    I have no advice but ask the question: What did the local people do when making pottery?
     
  3. Willem208

    Willem208 Tracker

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    Well I do not really know as there are extremely limited written sources that I can access. Hopefully sometime soon I can connect with local potters and learn.
     
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  4. MrFixIt

    MrFixIt Old Jarhead LB#42 Supporter Bushcraft Friend Bushclass I

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    I wish you luck in your endeavor, and I hope whatever you find out you will share with us.
     
  5. NevadaBlue

    NevadaBlue —- Roughian #7 -— --- Graybeard -— Supporter Bushcraft Friend Bushclass I

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    + 1 on sand. Common use of it. Have you done a ‘silt test’ on the clay? If not, drop a chunk of your clay in a jar of water, put the lid on the jar and shake it up. The various parts will separate in layers, giving you an idea of what you have to begin with. Might need a bit of silt too.
     
  6. DavidJAFO

    DavidJAFO Keeper of the Clubhouse swear jar Supporter

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    hello,
    @Willem208 I have a sample of your red clay I traded as so I can dry it out to a powder & use such for a pigment. I was a reading a .pdf about turning mud into brick & thought this paragraph may be of some interest to you. African red clays make quite friable pots that tend to flake immediately after firing. Over time the walls thin so much that pots become unserviceable. The flaking is likely caused by higher calcium and iron content in the clay, which would decrease plasticity and give the clays a somewhat higher shrinkage rate during drying and firing. To combat this problem, the red clay is mixed with sandy and organic-rich black clays. The black clays have greater plasticity due to a higher smectite and mica content and combat the flaking problem encountered when red clay alone is used. Only when the clays are combined is the desired working range of plasticity achieved while still retaining a low shrinkage rate.
    Regards
    David
     

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  7. Willem208

    Willem208 Tracker

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    I sure will share stuff later!
     
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  8. Willem208

    Willem208 Tracker

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    When I purified my clay there was like no silt or sand in it. This is all part of one big experiment.
     
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  9. NevadaBlue

    NevadaBlue —- Roughian #7 -— --- Graybeard -— Supporter Bushcraft Friend Bushclass I

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    Then you probably need the sand and a bit of silt. :dblthumb:
     
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  10. Willem208

    Willem208 Tracker

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    Where did you get the clay? And where did that PDF come from? It is what I was looking for all along. Also what you say about mixing clay is very interesting. Thanks for the information guys!
     
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  11. Willem208

    Willem208 Tracker

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    Where will I get the silt? Should I go dig up another batch as I remember my second try having a lot more silt in it?
     
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  12. NevadaBlue

    NevadaBlue —- Roughian #7 -— --- Graybeard -— Supporter Bushcraft Friend Bushclass I

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    I would dig some more and do a test on a raw sample. Like this:

    [​IMG]

    Then you will know what you have to begin with. I’ll dig out one of my books for you. It is called ‘Clay and Glazes for the Potter’. I will let you know what they say for obtaining ‘stuff’ for additives.
     
  13. NevadaBlue

    NevadaBlue —- Roughian #7 -— --- Graybeard -— Supporter Bushcraft Friend Bushclass I

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    Well, I did find the book. When I got out of the Army in ‘72, I was living in the Ozarks of Missouri and didn’t plan to go back to the mine where I had been working. One of my schemes was to use the wonderful red cave clay in the area to start a pottery. Needing to eat, raise kids and build a house changed that scheme. Sigh...
    So, I still have these books.

    2C6D78CF-510A-4C8E-A287-A1E844A4DF73.jpeg

    I am inserting the section on earthenware clay for you. I think this is what you want for ammo. When the author mentions grog, think broken clay, like crushed flower pots or bricks. Sand can be substituted for ‘flint’. The bottom line is, you need some ‘roughage’ in the mix to stop the cracking.

    BE369B2D-8194-4AF3-B1D8-E2CF31642F8F.jpeg

    6CE47E0C-EB83-4F21-A9DC-ECCD881C150F.jpeg

    C9EAB0A3-A4CD-4E47-8059-8AE84229AFEA.jpeg

    A407CB87-A329-4546-B5EC-B0859B82825D.jpeg

    AE5D3899-411C-452E-863E-329A28031845.jpeg

    Note that ‘aging’ the clay helps the workability of it too. Once you get the mix you need, let it sit for a few weeks.
     
  14. NevadaBlue

    NevadaBlue —- Roughian #7 -— --- Graybeard -— Supporter Bushcraft Friend Bushclass I

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    I read your first post again and think you should run with the mix you have. Try making some ammo and firing it in the coals of a good cooking fire. Show us what you get!
     
  15. Willem208

    Willem208 Tracker

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    Thanks so much for yiur help! Once it is ready I will go and roll some more glandes. I will mix in different amounts of sand into different clay balls, let them dry and maybe fire them to see what happens and what works.
     
  16. DavidJAFO

    DavidJAFO Keeper of the Clubhouse swear jar Supporter

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    hello,
    @Willem208 the red clay (I love that earthy aroma) it came from Africa as a Bushcraft trade. I posted a thread which I would need to look it up about the Himba people & their culture in relation to Bushcraft. The .pdf I was sent about the clay (?) I kept it on file for reference. My friend Linda who is an artist wants to use the pigment along with other natural stones that I've kicked for Bushcraft FSK purposes in her artwork. A group I was with a while back practising Bushcraft, they improvised a clay oven in the woods to fire pottery & fired clay ammunition similar to which the Roman Army (occupation of Scotland) possibly used. These specialized ‘Whistling’ clay slingshot ammunition (the size of Lemons) which were unearthed at a possible siege site at Burnswark Hill (southwestern Scotland) & may have been used for Psychological Warfare fired by the Roman "Slingers." The clay may have been mixed with more than one ingredient as to harden to ammunition, as dried clay would break upon impact. The Slingers ammunition at Burnswark Hill which was unearthed, the researchers believe that the dents were intentionally made so as to account for a whistling or buzzing sound as the projectiles flew across the battlefield.
    Regards
    David

     
  17. Willem208

    Willem208 Tracker

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    The best thing about the PDF is it is focused in an area just north of where I live! Thanks again.
     
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  18. Road King

    Road King Scout

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    If your making ammo try using quart if available its heavier temper. If you live near the coast use sea shells for temper. You will have to place them in a fire before crushing. Sand works well as a temper the ratio is roughly two parts sand five parts clay. When you change temper you will have to experiment a bit with varying temper. Keep in mind to not get too thick when firing. Hope this helps.
     
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  19. Joezilla

    Joezilla Guide

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    nick gordon, nick of the woods on meetup, knows clay really really well over a spectrum of environments. If you want, shoot me a PM and I can give you his contact.
     
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