What type of hair should be treated with violet-based colors?

Violet-based colors are particularly effective for gray, white, and salt and pepper hair because they counteract the yellow undertones that can often appear in these hair types. Gray and white hair can sometimes look dull or have a yellowish tint, which is where the violet undertone comes in. The purple hue serves to neutralize these unwanted warm tones, resulting in a brighter and more vibrant appearance. This color correction is especially necessary when dealing with the unique qualities and challenges posed by graying hair, making violet-based colors a preferred choice for enhancing the overall tone and look of this type of hair.