These Watercolour Blocks are glued on all four sides to prevent the need for the paper to be stretched. The perfect travel companion for the artist or student. Made the traditional way on a cylinder mould, this paper has a harmonious natural grain with evenly distributed fibres, resulting in a stable paper. Made of long 100% cotton fibres, it can absorb a lot of water without warping or causing the colours to bleed. In a technique exclusive to Arches Watercolour paper it is sized to the core with natural gelatin, which means it can be scratched without tearing or linting. This also preserves the lustre and transparency of the colours whilst preventing paints penetrating the thickness of the paper. It is truly a unique watercolour paper that is very forgiving, allowing the superimposing of washes and successive corrections, scratching and retouching.