Fire assays went wrong

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Dwf

Member
Joined
Jul 6, 2020
Messages
17
I ran four fire assays today in some new ore samples from my claim.
They all had sulfides, one more than the other three, so I roasted each sample for an hour each at 1100f.
I then mixed and fused them with legend mi ONGs high litharge fire assay flux with flour. Recipe below:
69% litharge
23.3% soda ash
3.5% bórax
2.2% silica
2% flour

I fused for 40 minutes after reaching 2000f.

The slag on two of them was unlike any I’ve seen before (granted I’ve only done a couple hundred fire assays) two were an opaque yellow, with bits of orange, with a metallic luster on top. One was dark brown with a metallic luster in top, and was was a fairly normal darkish green. Also all of the lead buttons were small (between 15-16 grams) I know I’ll need to add a bit of flour next time, but not sure what else to change to correct the slag. Or if it needs to be corrected?
6D5EFEAA-AF38-4A79-AFD4-5D35BFF82634.jpegBCCBEA73-4518-4C6B-A382-8EAB97DD2E8B.jpeg
On picture of each pour, along with the crucibles, arranged in matching order.
 
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