Aedelforsite is an obsolete mineral name historically applied to several substances, most notably to wollastonite (CaSiO₃), a calcium silicate mineral. It was first described from the Ädelfors mine in Småland, Sweden, but later research showed that the material was not a distinct species.
🌍 Origins and Naming
- Type Locality: Ädelfors mine, Alseda, Vetlanda, Småland, Sweden.
- Name Origin: From the locality “Ädelfors.”
- Historical Context: In the 19th century, several substances from Ädelfors were described under the name aedelforsite, including mixtures of wollastonite, quartz, and feldspar, as well as impure laumontite.
- Synonyms: Sometimes referred to as Edelforsite or Aedelforsite of Beudant/Retzius.
🔬 Chemical and Structural Properties (Wollastonite, the accepted mineral)
- Formula: CaSiO₃ (calcium metasilicate)
- Crystal System: Triclinic
- Appearance: White, gray, or pale green; fibrous, tabular, or massive habit
- Hardness: 4.5–5 on Mohs scale
- Specific Gravity: ~2.9 g/cm³
- Luster: Vitreous to pearly
- Stability: High melting point (~1540 °C), stable under normal conditions
⚙️ Geological Occurrence
Wollastonite (formerly called aedelforsite in some contexts) typically forms in:
- Contact metamorphosed limestones (skarns)
- Silica-rich metamorphic rocks
- Associations: Often found with garnet, diopside, vesuvianite, and calcite
🏭 Industrial and Scientific Importance
- Ceramics & Glass: Improves strength and reduces shrinkage.
- Plastics & Paints: Used as a filler and reinforcing agent.
- Metallurgy: Acts as a flux in steelmaking.
- Environmental Uses: Applied in soil conditioners and as a substitute for asbestos in some products.
📖 Historical Notes
- Confusion: Early mineralogists believed aedelforsite was a new mineral, but later analyses showed it was either impure wollastonite or mixtures of other minerals.
- Legacy: The name survives in historical literature but is no longer recognized by the International Mineralogical Association (IMA).
✨ Conclusion
Aedelforsite is now considered a synonym or misapplied name for wollastonite and related mixtures. Its story reflects the evolving nature of mineral classification, where early discoveries were later refined by modern crystallography and chemistry. Today, wollastonite remains an important industrial mineral, while “aedelforsite” is remembered as a historical footnote in mineralogy.
In short: Aedelforsite was once thought to be a distinct mineral but is now recognized as wollastonite or related mixtures, first described from Ädelfors, Sweden.
Sources: Mindat – Aedelforsite, Mineralatlas – Aedelforsite, ChemBK – Aedelforsite (Calcium metasilicate)
