Starlight itself seems to have a vast spectrum of underlying effects beyond the specific energies of the Constellation that created it. Under normal circumstances, those balance each other and form almost neutral light. Filtering this light to discard parts of this spectrum, allowing only the light to pass that grants a desired aspect could have many uses.
By fusing mundane Aquamarine gems and other materials together into a glass lens, it is possible to filter such effects into colored beams when putting the colored lens onto a placed Crystal Lens. This is not without a price, as an additional lens (which could be discarding parts of the Starlight itself) placed onto a Crystal Lens blocks more Starlight than the Crystal Lens alone.