A question about coal sizes....

I have a coal size question….

I was looking through other pages of our discussion forum here and grabbed this snippet:
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Anthracite
Name of size Diameter of mesh

Broken 4-1/2
Egg 3-7/16
Stove 2-1/2
Chestnut 1-9/16
Pea 1-1/16
Buckwheat 1 ½
Buckwheat 2 ¼
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OK. So why the difference from chestnut on up? I have a Harman insert and burn chestnut only because the previous homeowner told us to burn that. Can stove or egg be purchased locally? Is there an advantage of one size over another?
What about price? Is egg or stove cheaper per ton than, say, chestnut? How about burn properties? I’d imagine that you’d better be armed with a good bed of tinder/kindling if you wanna get a broken coal fire started?!

Gary in Pennsylvania

Gary--

They says the larger chunks of coal will provide more heat. I used chesnut coal for the past 3 years in my Harman but the nut coal mined by jxxxx is smaller, seems to have smaller pieces then it did 3 seasons ago. I've moved to stove coal. May take a little more to light but so far, it does seem warmer. I have heard of egg coal but I have never seen it offered for sale.

Funny how the stove coal costs a few bucks more per ton than does the nut & pea. I would think it should cost less? Maybe someone could explain. I would also think the smaller coal would provide more heat since it is more compressed in the firebox, but what do I know?

Cap wrote:Funny how the stove coal costs a few bucks more per ton than does the nut & pea. I would think it should cost less?

I don't think there is one specific reason but I'd imagine two factors are A) there isn't much of it, you can always make it smaller. You can't glue it back together. and B) it puts a beating on the equipment, at least for my part it does. I have aluminum chutes and one ding soon turns into a hole...

Big size hotter burns faster. Small size not as hot burns longer.