Clay Film from Drinking Water

This is a sample of a clay film that was seen in a drinking water sample from eastern Oregon. The film was evident in the water when a glass of the water was held in the light and a few glints of light could be seen as the flakes turned in the water. The flakes would sink to the bottom of the glass and could be collected by pipette. The film is colorless but is thin and layered resulting in the interference colors tinting the film in this image.