Iron Bar Purity Problems

[MurdochEx]

I'd put this in the bug section if I were sure it wasn't a hidden part of the newest update.
Are any of you getting unusual iron bar purity?
I'm trying to make a new rod with some 20% Sulpher ore (8.44,3.45,49.21,38.89).
I ran 2 runs through my smelter of nothing but that ore, no lime no other ore. The first load gave me an iron bar of 6% Mercury (11.97,41.89,25.75,20.38).
The second load gave me an iron bar of 12% Sulpher (7.24,12.72,45.12,34.92).
Is this some wacky new purity challenge like the new humus method?

[Alexivo]

Everyone is experiencing this, but it is not as bad as you think. The first thing I did after patch day was to go make myself some pure metal bars for dowsing rods. The first load of ore got me some unpure metal, so I threw in another load. Got mid pure metal out of that one. Tried again and finally got me some metal which was the purity of the ore I threw in.

What I think is happening is that the smelters are now keeping track of the alchemy levels of any partial pieces of metal. Usually, a smelter creates up to 1.70 (made that number up) bars of metal. It keeps track of partial pieces of metal for your next run. This is why sometimes you receive 2 bars, sometimes 1 bar.

I think the alchemy of any partial bars left over was just set at 25/25/25/25. When we ran our first load of ore through, it first used this residue when determining the purity. After flushing the system a bit with my pure ore irons, I was receiving progressively purer bars until I finally received my goal. Only took like 3 cycles.

Conclusion: residue left from partial bars affects succeeding bars. Make a few loads and all is well again.

[Burseig]

If you load your smelter with 15 ore and 10 lime, you get according to the wiki 180% of iron bar.
That means you get one and 80% of a second one stay in the smelter until your next loading.

If you have first unpure ore and then pure one, it's logical to expect some average metal bars because of that.