Gouache is an opaque watercolor based medium that has been used for centuries in fine art and design application. It produces rich, vividly colored paintings with a characteristically velvety matte finish. Gouache forms an opaque layer on top of the paper; it is not a stain like most watercolors.
       Gouache consists of pigments in a water-soluble binder (gum Arabic) with preservative and plasticizer (glycerin). The pigment in gouache is slightly larger than in watercolor and the ratio of binder to pigment is greater. Thinning with water creates a semi transparent look much like (aquarelle) watercolor. Using less water it is thicker and has a substance and body approaching oils. However, eliminating the oils means that it will not yellow with age so as long as permanent colors (versus designer colors) are used, permanency of color is comparable to, or some feel superior to, that of oils.
       Depending on the technique used, gouache can be a difficult, quirky, medium to master. Because the paint does not change chemically when drying it's vulnerable to water damage and should be framed under glass with acid free materials.
       Helen Stevens uses the finest 100% rag, ph neutral, hot press watercolor paper for her work. Combining this quality of paper with a professional grade of gouache creates works of lasting permanence and beauty.