mud snake
The red-bellied black snake, which is native to eastern Australia, is black with a distinctive pink-red belly.
Garter snake
I believe you are refering to a black rat snake.
Turquoise is a mineral.
Northern Black Racer
Eastern smooth green snake
I believe you are referring to the Grey Rat Snake.
That is the endangered Georgia Tube snake.
The Speckled King snake is a black snake with yellow or orange spots speckled over it's body. Another black snake with yellow spots would be Baby Eastern Black King Snake. Both are completely black with yellow speckles.
It depends on the snake. They can be blue, to brown, to black, to red. They can be solid or have very complex patterns. You should post a more specific question if you're asking about a certain type of snake.
If the stripes are light in color, maybe even off white it could be a CA king snake.