I'm wondering if anyone knows a source for Copper Sulfate in small quanities for making a Boreaux Mixture to spray Peaches and Apricots? The local nurseries have copper sulfate but it's only 7% and I understand that it needs to be at least 50%. My preference would be to get it in quanities of 5 lb. or less. If others are interested in this perhaps we could buy a larger quanity and split it up.