How to Make Gouache from
your Watercolor Paints
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¼ teaspoon measuring spoon
Teaspoon measuring spoon
½ teaspoon measuring spoon
Wooden stir sticks
Gouache sealed palette for storage
This is a quick and easy how-to for turning your watercolor paints into gouache. Marble dust is an ingredient used in paint making since the Rennaissance and is the inexpensive material that will give your favorite watercolor pigments the opacity of gouache. Little restaurant service cups, and stir sticks are a staple in my art studio for mixing small amounts of mediums and paints. Eye droppers are a great tool for adding water or other liquids to a mix in the studio without the worry of spilling liquid from a large jug.
1. Add ¼ teaspoon of marble dust to cup.
2. Measure 1 ½ teaspoon of tubed watercolor paint into a mixing cup and stir thoroughly with a stir stick. This is not an exact science; it's okay to eye-ball the 1/2 teaspoon if you don't want to dirty more measuring spoons. Basically your ratio is 6:1 watercolor to marble dust, so you use other measurements to meet your needs.
3. Add a few drops of distilled water at a time until the paint is the desired consistency. I do this by putting a few drops into the dirty teaspoon and add that into the cup to get more paint out of the spoon.
4. Using your stir stick, gently pour and scrape your paint mixture into your palette. Add a tiny bit more of distilled water or marble dust until desired consistency is achieved. Stir with a stir stick.
Be sure to note the name of the color in a corresponding box in your palette guide.
I'm sure the companies that make these watercolors might say that they can't guarantee products that have been altered, but marble dust has been a traditional filler in paints since at least the Rennaisance, so that's why I feel comfortable adding it to my paints.
Other watercolor pigments I'm enjoying as gouache are New Gamboge (which I use like Indian Yellow), Quin Magenta, Cobalt Teal, Buff Titanium, and Alvaro's Caliente Gray. It really opens up the range of colors you can use.
Above you can see my sketchbook with both the watercolor swatch of Daniel Smith Quinacridone Gold
Deep above and my homemade gouache below. The paintbrushes are my wonderful Rosemary and Co travel brushes available here.