1) Any iron-containing ore used for the extraction of iron. Most ironstones contain iron oxides (hematite, magnetite, or limonite) but other minerals such as iron carbonate (siderite) and even iron sulfide (pyrite) were sometimes used. Later, the name ironstone was used more specifically to refer to dense black iron oxide (magnetite) used to make imitation black pearls.
2) A dense, hard bluish white pottery. Ironstone china was very durable pottery and was used for common household bowls and crocks in the 19th century. It was patented by Charles Mason of Staffordshire, England as an inexpensive alternative to porcelain. Ironstone pottery contains flint, Cornwall clay, and cobalt oxide.
Synonyms and Related Terms
iron stone; minério de ferro (Port.)
Sources Checked for Data in Record
- Henry Hodges, Artifacts: An Introduction to Early Materials and Technology, Ronald P. Frye, Kingston, Canada, 1988
- Robert Fournier, Illustrated Dictionary of Practical Pottery, Chilton Book Company, Radnor, PA, 1992
- Website address 1 Comment: Olympus Microscopy Resource Center at http://www.olympusmicro.com/galleries/polarizedlight/pages/clayironstonesmall.html (Accessed Sept. 17, 2005)
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
- Susan E. Schur, Conservation Terminology: A review of Past & Current Nomenclature of Materials, Technology and Conservation, Spring (p.34-39); Summer (p.35-38); Fall (p.25-36), 1985