Watercolor painting Watercolor paint consists of four principal ingredients: a pigment; gum arabic as a binder to hold the pigment in suspension; additives like glycerin, ox gall, honey, and preservatives to alter the viscosity, hiding, durability or color of the pigment and vehicle mixture; and evaporating water, as a solvent used to thin or dilute the paint for application. The more general term "watermedia" refers to any painting medium that uses water as a solvent and that can be applied with a brush, pen, or sprayer. This includes most inks, watercolors, temperas, caseins, gouaches, and modern acrylic paints. The term "watercolor" refers
Gum arabic the desert locust. Sudan, Chad, and Nigeria, which in 2007 together produced 95% of world exports, have been in discussions to create a producers' cartel. In 1445, Prince Henry the Navigator set up a trading post on Arguin Island (off the coast of modern Mauritania), which acquired acacia gum and slaves for Portugal. With the merger of the Portuguese and Spanish crowns in 1580, the Spaniards became the dominant influence along the coast. In 1638, however, they were replaced by the Dutch, who were the first to begin exploiting the acacia gum trade. Produced by the acacia trees of Trarza