Recent Coal Quality

The coal I learned on was Pocahontas. It gave a clean fire and just a little white ash, we could run the forge for six to eight hours before
having a clinker problem.
We recently purchased from that same supplier and what we got looks _mostly_ the same as the old stuff but has some bigger chunks in it too. This stuff is producing large amounts of orangey-brown ash, I have to clean out the firepot after about 3 hours of work.
Now, on the day we purchased, the supplier was in the process of moving their coal piles and had bagged up all their loose smithing coal. We got the stuff from the top of the palettes, which I suspect was from the bottom of the pile (which would help explain the small rocks we've been finding).
So my question is: Should I attribute this unfortunate behaviour of this load of coal to the fact that it was the dregs of the pile? Or Should I come to the sad conclusion that the quality of Pocahontas coal has changed in the last few years?
- Carl West Prospect Hill Forge: The Blacksmithing Classroom http://prospecthillforge.com
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Personally, I think you were real lucky on the 6 to 8 hour stuff. We (Guild of Metalsmiths) think we have some alright coal, but after three hours or so, there'e plenty of clinker. We are currently getting ours from a mine in West Virginia, I think, in about 22 ton loads. I don't think that the quality of coal necessarily has changed, but Pocahontas actually describes a certain coal FIELD, not a particular analysis of coal (IIRC). Could it be the your supplier is now getting his "Pocahontas" from some other coal field that yields "similar" but not identical analysis? I think its like sticky tapes, where "Scotch Tape" has become a generic title for transparent sticky tapes in general and where "Pocahontas" is generic for "metalurgical grade". I'd sure like to hear what others have to say. Mark's Handbook (for mechanical engineers) has about 50 some pages about coal (at least my '70s edition does). It was pretty enlightening reading for me.
Pete Stanaitis ------------------
Carl wrote:

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Carl,
Coal forms in seams, and seams run out. Pocahontas is a field, or mine. With care you can find the stats on specific seams within the field. At this point it would be tough to figure if the junk was left in the truck they loaded the coal into, was from the yard where the pile was dumped, or was included with the coal in the seam.
Or, someone might just be confusing 'Pocahontas' with anthracite or bituminous, density grades of coal. Once the coal ships from the mine, it is tough to identify where it came from, unless you have the current seam assays and assay the lump in your hand.
Good luck on the next batch!
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Good points. Hard coal (Anthracite) or soft coal (bituminous). Martin Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Life; NRA LOH & Endowment Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
BradK wrote:

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