If it's different on both sides, that's probably why it's a #1. The #1s that I've had (two of them), one was identical to a lilywhite (I'm guessing they had all good stock at the time they were processing, but needed to fill #1 orders with lilywhite quality stuff - still have to make those price tiers, even if everything is good). The other was mottled on one side and more clear on the other (but it had a label, so I didn't try the back side). What's bad about the bad side, or is it just different?
You're talking about washitas and arkansas stones interchangable, but they're different. There is an old pike write-up on google somewhere that they're showing guys pushing carts out of mines (or following them) and they say that the pike washita mine comes out in giant clear sections. That's the mine area that Roy Underhill talks about being able to take stone off of the surface. I don't think it would run out in a few hundred years, but Norton thinks it isn't worth opening, and let's be honest - there's not much of a market. They'd sell $80 stones quickly at first and then none again. They're an industrial abrasives company, anyway - why would they want to fool with cutting stones. Now, Norton's stock for fine stones (arkansas, washita) has always been a lot more difficult to work with (to get a clear stone with no inclusions). They probably waste 10 times the stone volume of a finished 8x2 stone, but maybe that's just what they have in their mine.
I said something to that effect to someone who has been in the dan's factory, and he said that the black and trans material that dans has comes out in large uniform bricks that they can cut without as much processing. I think they just have better material to start with, but Dan also said the key is spending what it costs to go deep enough for the better stock, so it sounds more like a mine to mine thing.
I can't imagine that it's worth the trouble for Norton to keep selling natural stones when they make their money with manufactured goods and can control the process better. If they disappear, it doesn't sound like Dan's is going to run out of stock they can get unless the price drops.
The only two natural stones that I'm aware of actually depleting are the old upper-mine stones from some of the japanese mines (there are still lower strata stones) that have been open for several hundred years. Surface stone can't be used for that, either - if it goes through freeze and thaw cycles, it's junk. And, the true escher stones. There's plenty of other stone material in thuringia, it appears, but it's all darker and coarser. Escher closed when they ran out. Maybe there's more near it, but nobody has gone to the trouble of finding it (though scam artists still sell the junk they're pulling out as "original escher" or other names). There was still enough demand for the stones when the mine ran out that someone tried to set up a subsequent company sintering the dust from processing the original stones, but they're apparently no good.
