Scientific name: Au
Gold is a heavy, soft, yellow metal that is easy to work with. It is the softest metal, and is very dense, much denser than lead. Gold is very stable and is used to coat other more reactive metals to protect them, but its primary use is in jewelery. Pure gold is too soft to make jewelery out of, and is usually mixed with silver, copper and other metals.
A gradient is a smooth transition between one color and another. The picture shows a gradient from blue to orange in a dawn sky.
Green is the colour of the leaves on most plants. The colour green can be made by mixing blue and yellow paint. The frog in the picture is green.
Grey (also spelt gray) is the colour of weathered rocks and concrete paths. The colour grey can be made by mixing black and white paint. The cat in the picture is grey.
Indigo is a purple-blue color that was originally made from the indigo plant. Many types of jeans are dyed indigo.
Something is khaki if it is a dull greenish brown. It is frequently used as a color for uniforms, particularly in the military.
Scientific name: genus: lavandula
Lavender is a small bush with greyish leaves and pale purple flowers. Lavender is also the name for the color of the lavender flowers. Lavender flowers smell very nice and still smell nice when they are dried, so they are often used in potpourri.
Scientific name: genus: syringa
Lilacs are a group of flowering plants in the olive family. Most of them have pretty, light purple flowers. They are popular garden plants.
Something is monochrome if it is made up of shades of the same color.
Scientific name: citrus sinensis
An orange is the name for both a colour and a citrus fruit. Oranges are similar to lemons but are very sweet and can be eaten raw, squeezed to make juice, and can be made into marmalade. The colour orange can be made by mixing red and yellow paint.