Ultra-CR Cleaning Solution: Ultra-CR Polychem Ultrasonic Solution in a 55 Gallon Drum.  Ultra CR is a concentrated cleaning solution that’s mildly-alkaline, biodegradable, and blue in color (sometimes called the "BLUE Solution" or "Blue Stuff" or "Blue Ultrasonic SOAP").  Specially formulated for the cleaning of jewelry.  This ultrasonic solution works well with all precious metals, gold, silver, platinum, copper and brass. Ultra-CR is made to remove easily all polishing and buffing compounds.  Solution is concentrated and long lasting, and should be diluted with water as needed.  Recommended mixing ratio is approximately 1part to 10 parts water. 

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