It shows color.
It happens by the refraction of light.
You will see what some people call a rainbow, the differing refraction of light frequencies
it is refraction
Refraction
When light passes through water, it slows down due to the change in medium. This causes the light to refract or bend. The amount of refraction depends on the angle at which the light enters the water.
" The light is bent by refraction, caused by the medium through which it passes"
Refraction
There will be refraction when light passes from one substance to the other (for example, from air to water), when the two substances have different indices of refraction, and when light passes the surface at an angle. In other cases, there is no refraction.
Refraction
Reflection occurs when light bounces off a surface, changing direction but not entering the material. Refraction happens when light passes through a material and changes speed, causing it to bend.
In reflection the light bounces bach; in refraction the light passes through, but is bent at the interface.
Light can be both reflected and refracted when it passes through a transparent medium. Reflection occurs when light bounces off the surface of the medium, while refraction happens when light changes direction as it moves through the medium.