Thermaguard is made of Silquar®, a unique ceramic material which forms a protective blanket around any stone or jewel while adjacent parts are being soldered or heated. Resists temperatures up to 2000°F. Odorless and non-toxic, Thermaguard is easy to use and eliminates the mess and clean-up of creams, brush and spray-on solutions, and other less effective products. Each 2 oz. jar is good for hundreds of jobs because Thermaguard is reusable.