Main Discussion Area > Primitive Skills
native pottery
iowabow:
865 very slow drop
iowabow:
775 is where we are now.
So our careful drop is going way slower than 50 per hour. Interesting data to be sure. This means that there is a lot of heat work taking place after stopping. Now the cone or heat work is different than degrees. What that means is that the longer an object is exposed to heat the more it will change that object. So if you put your hand over a fire then remove it fast there will be no heat work but leave it over a flame for a long time you will have hand steak. So although we only reached 1100 which is cone 22 we most likely hit cone 19 because it stayed so high for so long. Now with that said the very very slow drop is making movement in the clay safe because it is occurring very slowly. Based on this there should be no breakage due to rapid cooling. So if the pot is broken it would be safe to guess that rapid heating was the culprit.
Conclussions at this point:
The fire pit was shallow so as to reflect early types of firing and temps were low. To make a pot more durable long heat holds had to take place. Also fire tending was a must to maintain a temp above 1000 degree. My best guess would be a hold of six hours.
iowabow:
An hour later an we are at 771.
iowabow:
OK now i have some cool ideas this is clay from the pit. One is fired the other is not. The pot is made from different colored clay. I think i can decorate with a watered down clay (slip) and make orange lines and forms..
iowabow:
With the fire not dropping i am getting worried about hot spots with other areas cold. I decided to tuck in the fill on top to cut off oxygen.
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