This deoxidizing flux keeps metal clean during melting (Gold, silver, etc) and pouring . Can also be used for preparing melts for assaying. Specially prepared for making a paste; dissolves easily. Borax is also used mixed with water as a flux when soldering jewelry metals such as gold or silver. Also used to glaze crucibles and casting process. You will need to glaze your crucible with borax before you melt any metal in it. This ensures that your metal doesn't stick to the ceramic crucible. Net Weight 8 Oz (1/2 Lb) Borax (Sodium Tetraborate Penthydrate) TECHNICAL GRADE FOR PROFESSIONAL USE ONLY First Aid: Eye Contact: Flush Eyes immediately with plenty of water. Skin Contact: Wash skin with soap and water Ingestion: Drink Large quantities of water Keep Out Of Reach of Children Store in a cool and dry Place. Not for Household, drug or food uses.