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Rainbow or Iridescence Markings on Glassware

Possible Solution

Why is this happening to my glasses?

The iridescence of glassware results when light waves going through the glass are refracted either by varying thickness from erosion or build-up of the glass. Some causes of this include:

  • Disilicate deposition. Detergents with a high level of disilicate can cause silicate to build up on glassware. Avoid detergents with a high level of disilicate.
  • Excessively soft water. Detergents are designed to expect some hardness to be present. If water is very soft and/or high amounts of strong detergents are used, the chemistry provided to address the water hardness instead impacts the dish load or dishwasher itself. Test water hardness and ensure it is within the proper range. If using powder or liquid detergents, don't use too much. Consider using premium detergent packets that typically have chemistry designed to minimize damage.
  • Using long or hot cycles. If uncertain about the quality of items, try using quick, low temp cycles to minimize damage. It may be necessary to evaluate the trade-off between performance and damage if items are of very poor quality. Consider the use of premium detergent packets which usually have chemistry to minimize damage.




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