A form of clay that is a very effective wine fining agent, one that usually clears wine in 1 to 3 days. Enough for 15 gallons of wine. Added right before racking your wine from a primary fermenter to a secondary.
To clear 5 gallons of wine in a primary fermenter, first make sure it has reached final gravity. Use 3 teaspoons of Bentonite and mix into 1.5 cups of boiling water in a small saucepan. Turn off the heat, mix thoroughly and let dissolve overnight as it cools with the lid on. The next day transfer your wine to a secondary and mix in the Bentonite solution to help clear your wine.