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Jesse John Cook

Preparing for first smelt.

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Hello everyone! I just joined the forum and if this is better suited to the beginner section just let me know. I've already learned a great deal here so thank you to everybody for spending your time sharing with the community.


I have some questions as I'm preping for my first smelt and there is a lot to learn. I started by collecting what I believe is ore. (I posted some pre-roast pictures, if someone knows what it is I would love to know) I noticed it on a hike and checked it with a magnet and it was already slightly magnetic. I roasted golfball to softball sized pieces for about 4 hours. I've now started to break it up, however it doesn't break apart as easily as some ore I've seen in videos, but a few hard hammer swings will do the job. My first question is what size should the ore be? I've watched videos and read articles but ore size seems to vary. A lot of videos seem to indicate the ore is crushed to a fine powder. However some resources indicated ~1cm, and catalan furnaces use lump ore (I understand these work differently to a stack, I was just hoping for some clarification on why the ore size varies.) From one article it sounds like the ore should be broken up slightly then roasted again before crushing to final size, what is the most common process? I'm sure I'll have more questions soon but it'll take me awhile to get everything ready. Next step will be a charcoal retort build, I'll post about that when I start.







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I can't really say what it is from the pictures, but possibly maghemite, a metamorphosed hematite.  It will be harder that the usual limonite/goethite brown ore that crushes so easily, almost as hard as magnetite which really doesn't like to be crushed.  Coarse sand slightly smaller than aquarium gravel is good for size.  Did it get to a good full red heat during roasting?  

I will be enduring spotty communications for the next week or so, so be patient with further questions, please!  And welcome aboard!  Hopefully Lee Sauder and Mark Greene will see this and chime in, they are far more experienced with difficult ores than I am.

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Awesome thanks! The roasting fire didn't get too hot until the end, maybe I'll roast the smaller stuff again to be sure. Thanks for your quick reply, no rush on my part I'll have spotty connection until monday anyways.

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I'm certainly no expert on the subject. But since no one else has posted, i'll chime in:

From my understanding you want to roast the ore- ideally bringing it up to a cherry red or-there-abouts for bit, followed by crushing it to "pea sized". Smaller is good. Some slightly larger pieces are ok too. No need to roast a second time. Just the once to force molecular water out and to start the oxide changes. My experience is with Lee's furnace design that he discusses in the papers that can be found on his website, so I can't speak to other furnace designs.

I look forward to seeing your progress on a charcoal retort. I'm starting to gather the necessary information to start building one as well, so I would be interested to see another build. 

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