Platinum Classic Forest Black Ink Bottle 60ml. Enjoy writing yet again with Classic ink from Platinum pens. The ink color is bright when you start writing, and then becomes gradually black. It is also highly water resistant and suitable for permanent preservation. Please note the ink is made with tea leaves and sometimes there is a bit of sediment in the bottom of the bottle. Since a natural ink, the color may vary slightly from batch to batch. There is naturally occurring iron in the ink but is not considered to be an Iron Gall ink.