Twice when I tried to buy 50 pounds of
granite chicken grit, the warehouse guys gave me oyster shell grit.
Or some other kind of shellfish grit.
Maybe double-screened crushed stone would work as well (dust and sand removed), if you can't find chicken grit.
Since I started screening my own pine bark shreds and nuggets, I haven't bought much grit. But I don't grow alpine plants.
P.S. Have you seen this vendor of Western US wildflower seeds? Huge variety of plants I never heard of before.
http://www.alplains.com/
