Refining your mineral samples
Mining is the process of extracting minerals and other valuable materials from the earth. The extracted materials are then processed through refining, which separates and purifies the minerals from other unwanted materials. Mineral refining involves various processes such as crushing, grinding, and concentration to extract the desired minerals. These minerals may further undergo smelting and refining processes to produce metals with high purity and commercial value.
Avantor offers carbon bonded silicon carbide crucibles for metal melting in a wide variety of shapes and sizes as well as refining flux ingredients and flux formulation services to support your refining workflow.
Flux Ingredients
Anhydrous Borax is used in almost all Fire Assay fluxes. It lowers the fusion temperature and aids in the formulation of slag.
Where appropriate Fluorspar is used in Fire Assay flux to improve fluidity of the slag by suspending any infusible particles.
Small lead pellets with definite amount of silver which may be added to crucible before fusion or tapped into cleaned lead buttons before cupellation.
Potassium Nitrate is used as an oxidizing agent during mineral fire assay and refining.
Silica flour is added to samples to protect the crucible in the fusion phase of the Fire Assay process. Insufficient silica levels will result in increased and erratic crucible wear.
Silica sand is added to samples to protect the crucible in the fusion phase of the Fire Assay process. Insufficient silica levels will result in increased and erratic crucible wear.
Silver foil is added to sample/flux mixtures as an inquart agent facilitating the collection gold or silver in fire assay.
Silver nitrate power is added to sample/flux mixtures as an inquart agent facilitating the collection gold or silver in fire assay.
Silver sulfate power is added to sample/flux mixtures as an inquart agent facilitating the collection gold or silver in fire assay.
Soda ash (sodium carbonate) is a basic component found in fire assay flux. In either light or dense format, it reacts with silica based minerals to form fusible sodium silicates.
Refining Crucibles
Silicon carbide crucibles are used in the mineral refining process for their durability and resistance to thermal shock due to quick temperature changes in a refining furnace.
Refractory cement is used in the mineral refining process to stabilize the crucible when placing it inside the refining furnace.