0 a chemical used in industry and medicine. In medicine, barium sulfate is swallowed by a person just before an X-ray is taken of their stomach and bowels, so that these organs can be seen clearly.
The open circles show the chromaticity of light reflected from a plaque of barium sulfate.
Liquid suspensions of barium sulfate are non-toxic, apart from a small risk of producing a disturbance in bowel function for 48 hours after ingestion.
Barium sulfate is used in some applications too.
An exception is the administration of magnesium sulfate in barium chloride poisoning, where sulfate binds to barium to form insoluble barium sulfate.
The brightening occurs because barium sulfate is in the form of a fine precipitate that scatters light back through the silver image layer.
Shortly after, the process was improved; barium was removed chemically, by double precipitation from a solution as barium sulfate.
The paste contains carbon black, "blanc fixe" (barium sulfate) and lignosulfonate.
In colorimetry barium sulfate is used as a near-perfect diffuser when measuring light sources.