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  1. Yes! thanks Tyler! A chemist friend of a friend of family bounced back that it's more likely from iron. Fascinating stuff. Nevertheless, I haven't been able to recreate it under other lower temperature circumstances. Seems the 1500-1600F range is important. Also, I checked it a day after passing through the coffee filter and it's dropped out on it's own. Still at 12+pH, it's now a very clear slight yellow w/ what could be rust or Cu on the bottom. Photos below of the same jar 24 hours apart.
  2. Thanks all 3 for pitching in on this. Ash source was from the wood stoves of friends and coworkers - from common mixed hardwoods native to my part of WNC. Nothing fancy there. Filtering has little effect save for slightly improved clarity. interestingly, after filtering I noticed some yellow staining on the inside rim of the original mason jar I had stored it in , just above the fill line. Going to check the homebrew shop in the morning for sodium metabisulfate. Thanks for the tip! Amphoretic - new word for me. My pH strips indicate I'm in the 12 range on both samples. Seems clear this is CuOH2 then? It is definitely the characteristic blue/green I've seen from acid flux stains on copper pipes. Still, my soil application tests show such low concentration of copper, I'm baffled by the aggressive color change. Tomorrow I'll repeat the same process at a lower temperatures. Will repeat with an all new known-species of wood ash sample at 1500F for fun. Will post updates if anything interesting comes up. thanks again everyone
  3. I'm not currently a ceramics artist (though upon reading, this about mixing glazes is fascinating) but rather I'm exploring wood ash chemistry for an upcoming "Waste Not" workshop at our farm in Western NC - these workshops are about diving deep into applications for what is conventionally considered a waste product. I'm admittedly in over my head a little with this one. I've stumbled across a brilliant green (with a touch of blue) color after soaking wood ashes that have been calcined for 2 hours at 1500F. What is causing this? Some details of the experiment: I have two samples repeated 4 times. One sample is presoaked wood ashes - soluble compounds have been removed for making potash 'lye' water. The other was not yet soaked. Each 1 cup sample was roasted at 1500F for over two hours. The presoaked, calcined ash was soaked again with water (in an exploration of portland cement alternatives) and the excess water was clear and very alkaline. The un-soaked, calcined ash was soaked w/ water revealing almost instantly a brilliant green color in the excess water. I've had soil application tests that reveal each soaked and unsoaked sample have similar amounts of Mn and Cu... two elements I suspect would attribute to the green color but are not necessarily soluble in water. Is it that I've oxidized the copper and therefore somehow made it soluble? and that only a very small amount (135ppm dry, 165ppm soaked ash) is enough to change color that dramatically? My plan is to decant and recrystallize what's in this small amount of vibrant green water. Exercising the normal precautions - glasses and gloves - should I be otherwise concerned? I'm asking the ceramics glaze as I suspect what I've stumbled on was perhaps some kind of middle ages technique someone here may be familiar with? I understand that in your craft, impurities in the glazes can have a huge impact, and I know wood ashes have a role in some glazes. Is this particular case at all relevant to your work? Thanks for reading -dan
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