It is actually a phenomena when a light ray travels from an optical denser medium to a relatively denser medium. When the light ray is incident on the surface separating the two media at an angle greater than the critical angle for that pair of media, the light ray is reflected back to the previous medium at an angle equal to the angle of incidence with respect to the normal drawn to the surface separating the two media. Unlike reflection from a plane surface,here is no loss of energy and the reflected ray is equally bright as the incident ray.
1>A diamond shines when viewed from certain angles.
2>A glass vessel when submerged in water with only the rin above the surface, the rim shines when viewed from certain angles.