noun
- A red or reddish-brown iron oxide powder obtained by heating ferrous sulfate or by roasting iron pyrites; used as a pigment and polishing agent.
Usage: technical; chemistry; also called jeweler's rouge or red ochre in some contexts
Examples
- The jeweler used colcothar to polish the silver bracelet to a high shine.
- Colcothar is commonly employed in the manufacture of fine abrasive compounds.
- The red pigment colcothar has been used in paints and ceramics for centuries.
- Industrial suppliers stock colcothar in various grades for different polishing applications.