Remove the inner membrane from each cleaned, cracked and used eggshell and crush lightly in a mortar and pestle. You don't need to crush the eggshell into a powder, just into small pieces.

Place eggshell bits in a one quart mason jar and add 1 pint of cider vinegar and close the lid. Make sure you use a one quart mason jar as the mixture tends to foam up so you will need the extra room in the jar.

Soak for at least a week, then use as desired.

Leave eggshell tincture on the counter or in the pantry. No need to refrigerate.