What is a Tortillion used for in art?

A Tortillion is a specialized art tool primarily used for blending and shading in drawing, particularly with charcoal, graphite, or pastel. Its tapered, rolled paper structure enables artists to seamlessly smudge and soften lines, creating smooth transitions and subtle gradations in tone. This technique allows for a greater depth and realism in artwork, enhancing the overall visual quality.

The other options pertain to different tools or techniques. For example, cutting paper typically involves the use of a craft knife or scissors, while applying ink might involve the use of brushes or pens. Measuring proportions is often facilitated by tools like rulers or calipers, rather than a Tortillion. Thus, the primary function of a Tortillion as a blending tool distinguishes it from these other options.