<span>A
mineral has to be naturally occurring, inorganic, solid, have a crystal
structure, and have a definite chemical composition. Coal is not a
mineral because it is carbon-based and came from fossilized plants. That
proves that it is organic and has no definite chemical composition,
defying two rules you would need to follow to be a mineral. Glass is a
non-crystalline solid. This means that the atoms are not arranged in a
regular and repeating pattern. A mineral by definition possess a
crystalline form, it has its elements arranged in a regular and
repeating pattern.</span>
Nicotine, once in the brain, will work specifically on nicotinic receptors in the brain. However, there is a common "addiction" pathway in the brain that pretty much all addictive substances go through.
