![Make Paper Marbling with Carrageenan](https://cdn.slatesource.com/9/d/7/9d7181e7-14b7-4c6d-bd74-3f66557181d1.webp) # Make Paper Marbling with Carrageenan - [Made in Slatesource](https://slatesource.com/u/kairenner/make-paper-marbling-with-carrageenan-865) - By [KaiRenner](https://slatesource.com/u/KaiRenner) - Arts & Culture - Created on Mar 20, 2026 > Every marbled sheet is the only one of its kind. That is not a selling point. It is the nature of the medium. > > — KaiRenner · 26th of April 2026 ## How Carrageenan Marbling Works Traditional paper marbling floats pigments on a thickened water surface called a size. The size holds the pigments in place so they can be manipulated into patterns before a sheet of paper picks them up. Carrageenan seaweed powder is the standard modern size — it thickens water without making it sticky, and pigments sit on the surface rather than sinking. The paper must be pretreated with alum to accept the pigment transfer. **1** Tablespoon **1** Tablespoon Prepare the Carrageenan Size Mix carrageenan in water 24 hours before marbling to allow full hydration. ## Prepare the Carrageenan Size Add 1 tablespoon of carrageenan (lambda or kappa) to 1 liter of cold water in a blender. Blend for 1 to 2 minutes until fully incorporated. Pour into your marbling tray and let sit for 24 hours — carrageenan needs time to fully hydrate and develop the right viscosity. Before use, skim any foam from the surface with a strip of newspaper. Size the Paper with Alum Brush alum solution onto paper and let dry completely before marbling. ## Size the Paper with Alum Dissolve 1 tablespoon of alum in 1 cup of warm water. Brush a thin, even coat onto one side of your paper using a wide watercolor brush. Let dry completely — at least 1 hour. The alum-treated side is your printing side. Alum creates a mordant layer that causes pigment to bond to the paper during transfer. Drop and Manipulate Pigments Drop inks or gouache onto the size and create patterns with a stylus. ## Drop and Manipulate Pigments Add a few drops of ox gall to your gouache or watercolor to help pigments spread on the size surface. Drop pigment from a brush tip or eyedropper — it should spread into a circle on contact. Add additional colors. Use a comb, stylus, or toothpick to pull and swirl the pigments into patterns. Work quickly — the pattern drifts and merges on its own. Lay Paper and Lift Lower the alum-treated side onto the size, press gently, then peel up. ## Lay Paper and Lift Hold the paper by two corners, bow it slightly, and lay the alum side down onto the size from one edge, letting it contact the surface progressively without trapping air. Press gently. After 30 to 60 seconds, peel up from one corner in a smooth motion. Rinse immediately under a gentle stream of cold water to remove the size. Hang to dry. What You Need 0% Lambda carrageenan powder Alum (potassium aluminum sulfate) Shallow tray larger than your paper Gouache or acrylic inks with ox gall added Wide paintbrush for alum sizing Stylus, comb, or toothpick for patterning Watercolor or text-weight paper Ox Gall Is the Key Spreading Agent Without ox gall or a synthetic equivalent, gouache sits in tight globs on the size rather than spreading. Add ox gall drop by drop to each pigment until a test drop spreads to a 2-inch circle on the size. Too much ox gall and colors repel each other and refuse to layer. Too little and they clump. > The pattern you make and the pattern that transfers are never quite the same. Work with that. > > — KaiRenner · 26th of April 2026 [Paper Ink Arts — Introduction to Carrageenan Paper Marbling](https://www.paperinkarts.com/marbling.html?utm_source=slatesource)