This designation represents a specific shade within a professional hair coloring system. Generally, the first number (7) indicates the level, referring to the lightness or darkness of the color, with 1 being the darkest (black) and 10 the lightest (platinum). The number following the decimal (1) signifies the tone, reflecting the nuance or hue within that level, such as ash, gold, or copper. This precise numerical system allows for consistent and predictable color results.
Standardized color numbering systems provide a universal language for hair professionals, enabling clear communication and accurate replication of desired shades. This precision eliminates ambiguity and guesswork, contributing to client satisfaction and professional efficiency. The development and adoption of such systems reflect the evolution of the hair coloring industry towards greater sophistication and technical mastery. Understanding this system allows for informed choices regarding color selection and maintenance.