Determining the refractive index of prisms using a spectrometer generally focuses only on basic measurement procedures without analyzing the relationship between minimum deviation, light dispersion, and sources of measurement error. In addition, studies that integrate the determination of refractive index, dispersion curves, and evaluation of scale reading accuracy in a single experiment are still limited. This study aims to determine the refractive index of a solid prism materials using the minimum deviation method and to analyze the phenomenon of light dispersion based on the resulting color spectrum. The method used is a laboratory experiment with a prism spectrometer and a mercury (Hg) polychromatic light source, with a prism apex angle of 60°. Measurements were taken on the yellow (λ = 5770 Å), green (λ = 5461 Å), and purple (λ = 4047 Å) color spectra through readings of the main scale and vernier scale, then analyzed quantitatively using the minimum deviation equation and dispersion curve. The novelty of this study lies in the integration of minimum deviation analysis, light dispersion, and measurement error evaluation in a single series of spectrometer experiments. The results of the study show that the mean prism refractive indices are n = 1.6384 (yellow), n = 1.6218 (green), and n = 1.6872 (purple), respectively, consistent with the refractive index range of dense flint glass and confirming the wavelength dependence of the refractive index. This study proves that prism spectrometers are effective in determining refractive indices and characterizing the optical properties of materials experimentally and can serve as an effective contextual experimental model for physics education.