Method:

You will need 2 teabags and 6 iron tablets (Iron Sulphide) Brew the tea for 1/2 hour in 250 mL of boiling water. Dissolve the tablets in 2 teaspoons of hot water. Add the iron solution leaving undissolved bits behind (note the fizzing). Leave overnight.

You have just formed Iron Tannate from the tannic acid in tea!

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