Description Platinum Cassis Black fountain pen ink is a muted, blackened shade of red and comes in a 60ml glass bottle with a built-in reservoir for easy filling of your fountain pen. Platinum Cassis Black ink is an iron gall formula that will darken in color over time. Platinum ink is made in Japan and is very popular for its consistent performance. Interested in this color? Check out our thINKthursday blog post for more info! Having trouble deciding between colors? Use our Ink Comparison Tool to quickly and easily view different colors side by side. We offer Free Shipping on all orders over $59 for US customers, and for orders over $250 for our Canadian customers.