Dark Crystal is an exceptional cleaning solution due to its extraordinary traits. This product also works as a quartz cleaner as well, cuts away at any build up or residue. This solution is 100% plant based, a true non-carcinogenic green product also has no expiration. Heating up soution gives you faster results, set in microwave for 1-3 minutes or until boiling point. Orderless and very safe on the ozone layer, contains no phosphates.