Searching out the local places for rock dust and came across a nursery supply about 1/2 hr. drive away on an a web search. They don't have rock dust listed but they carry azomite dust and so I emailed them and inquired about rock dust such as granite dust. The guy emailed me back with this message: Any links that you all may have to help educate this guy? I am fairly new to rock dust as well so I am not sure what link is good info. Thanks.