What are inorganic pigments primarily made from?

Inorganic pigments are primarily made from ground minerals, which provides their distinctive colors and properties. These pigments derive from naturally occurring sources such as metal oxides, earth clays, and other mineral substances. The use of ground minerals allows for a wide range of colors, excellent stability, and lightfastness, making them ideal for various artistic applications.

The other options do not accurately represent the composition of inorganic pigments. Organic solvents (the first option) are not material sources for pigments but rather substances used to dissolve or suspend pigments. Plastic compounds could refer to synthetic materials often used in art supplies but are not the basis for inorganic pigments. Natural dyes, while they can be sources of color in other contexts, typically consist of organic (plant-based) materials rather than inorganic minerals. Thus, the composition of inorganic pigments is firmly rooted in the use of ground minerals, making this the correct choice.