"[0024] The quantity of pigment dispersed in the mass of the ceramic is preferably between 1 and 5%, preferably 2 to 4%; the lower values yield more pastel shades, while the higher values yield brighter shades.
[0025] For example, ceramic timepiece components may be obtained in the red range by using gold nanoparticles with an average diameter of between 10 and 15 nanometers dispersed in a zirconia or zirconia/alumina matrix."

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