Dark Sienna, being the lighter of the two Bob Ross brown colors, is frequently used in a marbled mixture with Titanium White, to create highlights for cabins and trees. The creative possibilities are countless! One of fourteen warm clean colors, yielding endless numbers of natural combinations in a smooth yet firm consistency necessary to the Bob Ross Wet-on-Wet TechniqueŒs. No other paints can accomplish what these do, and every batch is individually tested for perfection.