Question

Why will sulphur particles scatter blue light?

Answer 1

Tyndall scattering applies to larger colloidal particles, and it too is dependent on the fourth power of the frequency of the radiation and preferentially scatter blue light, so the yellow of the sulphur would be less apparent. Finally, particles coalesce and scattering becomes less important than the reflection of the larger particles. Perhaps sulphur nano-particles behave a bit differently from bulk material due either to quantum effects or to surface effects.