The base is the key chemical molecule that determines the tone. Colorists recognize 11 levels, numbered from 1 (black, absent in nature) to 11 (platinum, a professional creation).
Key fact: On any color package, the base is the first number listed—the lower it is, the darker the shade.
Two people with identical base tones can display strikingly different colors due to unique reflections.
Key fact: This is the descriptor that defines the color, such as "golden chestnut."
Shades represent variations in reflections. Professionals blend them or adjust ratios to craft custom hues. On at-home dyes, the shade follows the base number (e.g., 7.2 for ash blonde).
Key fact: Shades fall into two main families: cool (blue-leaning) and warm (red-leaning).
The most widely used method, oxidation coloring works in two ways: it generates new color (via ammonia or oils) while oxidizing hair's natural melanin by lifting the cuticle scales to deposit and lock in pigments.
Key fact: For permanent changes beyond 2 tones, oxidation color is essential.
Insights courtesy of Frédéric Mennetrier, L’Oréal Professional color consultant.
