Does white ice mean the water is dirty?

Question

When you freeze water that is supposed to be filtered and the ice is very white does that mean the water is dirty or that there is just alot of air bubbles in the ice?

Answer 1

There may be tiny air bubbles within the white ice.  Another possibility is that the water had a high mineral content.  As water freezes water molecules link up in chains and crystals driving the minerals ahead.  The last thing to freeze is the mineral rich water where freezing crystals meet.  When a mineral rich ice cube is melted in a glass of water the minerals may fall like snow flakes.  If a frozen lake has high mineral content, the first ice to melt is the mineral rich ice between grains of pure water or crystals and the ice may become weak and crumbly (and is often called rotten ice).

Answer 2

It means that the air dissolved in the water came out of solution as it froze, forming bubbles.

Answer 3

It's probably just air bubbles that came out of solution as the water cooled and froze.

You can check by watching a cube melt, though. If the white stuff remains as it melts, then it is particulate matter. (I'm guessing not, though. The crud in the water would've settled out during freezing, and not remained suspended like gas bubbles.)