# Difference between revisions of "Nature of light"

The beaty of a gemstone depends almost entirely upon the way it effacts the light. The fire of a Diamond and the play of colors in an Opal are just two examples.

Scientists recognise two different theories to explain the way in which light is transmitted:

• The electromagnet wave theory
• The quantum theory

Both theories are important to learn so you may understand the causes of color in gemstones.

## The electromagnetic wave theory

### Basic

This theory was developed by Dutch scientist Christian Huygens and later explored by others.

Light is a form of energy traveling in a wave motion.
It can be compared to what happens when you throw a brick in a puddle of water: the watersurface starts to vibrate and these vibrations cause circular waves.

[[Image:]] (which explains wavelength and amplitude)

The wave motions of light are not circular but spherical.
We can't see the light because:

• It travels too fast. The velocity of light (in air) is approx. 300,000 km/second.
• The individual waves are too small.
tansversal light

The ligh waves are transversal . This means that light travels in all directions in a straight line from its source.

There is a relationship between wavelength and color of light which is explained by what we call the electromagnetic spectrum.