I love your idea of Boron drops in a dropper.
I've been running the numbers different though.
If 1 ml = 20 Drops
That means there are 2000 drops in a 100ml bottle
So at 1 drop per dose that = 2000 DOSES
30mg Borax (0.03g) = 3mg Boron (0.003g)
That would mean you need 60grams Borax dissolved in 100 ml water to provide 2000 doses of 3mg Boron.
So to get around the problem is simple
Aim for 10 drops for each 3mg Boron dose.
2000 drops ÷ 10 = 200 doses of 3mg Boron
200 × 0.03(Borax in gram) = 6 grams Borax
Needs to be dissolved in 100ml water
Now that is very doable.
So if you want 3mg Boron a day.. just drop 10 drops in a glass of water.
That's a 200 day ( 3mg/day) supply
100 day (6mg/day) supply
Yes a 5ml teaspoon takes 5ml/5gram water.
Keep in mind that
Water 1 cubic meter = 1000kg
Borax 1 cubic meter = 1730kg
(Thats 42.19 % more than water)
So if 5ml teaspoon takes 5grams water
A 5 ml teaspoon(not rounded) would take 7.10 grams of Borax
I won't stress the extra bit too much..as I've seen info that we could basically take one or two teaspoons a day without side effects.
But once again AWESOME IDEA for the dropper..would make life sooo much easier.
For 1 drop to equal 6 mg of Boron, 2000 drops must have 12000 mg of Boron or 1.2g. But Borax is not pure Boron. 25 to 30 mg of Borax contains 3 mg of Boron.
To make the calculation simpler I will choose 30 mg. That means 1 mg of Boron is contained in 10 mg of Borax. We need 1.2 g of Boron, which is in 12 g of Borax. You need 12g of Borax per 100 ml of water. I'm not sure that much Borax will dissolve in that much water. If not, add another 100 ml of water. Then you will have to use 2 drops to get your 6 mg of Boron.