Making your own copper sulfate solution of 1 mg contained copper per drop is very easy. Just measure out the blue copper sulfate crystals and the water.
This is about 5/8ths of a teaspoon, or 5 of the 1/8th teaspoons, or about 4.7 grams or 4700 mg of 99% pure copper sulfate pentahydrate (containing 25% copper by weight), or 1175 mg of contained copper being put into a 2 oz. bottle, containing about 591 drops per oz. or roughly 1182 drops, making roughly a 1 mg per drop solution.
4700 mg x 25% = 1175 mg
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