A reference material for and a method of calibrating at least one Raman spectrometer are disclosed. The reference material includes quantum dots distributed in a transparent condensed phase material such that light emitted by the reference material in response to receiving excitation light having an excitation wavelength provided by the Raman spectrometer(s) has a predetermined spectral intensity distribution in a spectral measurement range of the Raman spectrometer(s). The method includes designing, manufacturing and providing the reference material, determining an emission spectrum of the reference material, and calibrating each Raman spectrometer by determining a reference spectrum of the reference material and by adjusting a determination of spectral intensity values of intensity spectra performed by the Raman spectrometer based on the reference spectrum and the emission spectrum of the reference material.