Tom's ink is not made from walnuts. The ink is walnut coloured made from premium light fast pigments that will not fade over time. The ink is also acid free. Genuine walnut ink is highly acidic and actually eats the paper over time. The drawings of the Great Masters were made with genuine walnut ink which was black when it was freshly made over time it faded to the beautiful sepia tones that they are now. Tom's Walnut coloured ink replicates these sepia tones. Our ink is water-based allowing you to achieve darker tones with layering techniques or lifting to lighten.