Aquacreptite (of Shepard)

Mg4Fe2Si6O19·8H2O with some Al2O3, or near
IMA status
  • Grandfathered
  • Questionable

Where it forms, where it's found

2recorded occurrences
Source · OpenStreetMap

Physical

Hardness
123456789102.5/ 10 MOHS
  1. 1Talc
  2. 2Gypsum
  3. 3Calcite
  4. 4Fluorite
  5. 5Apatite
  6. 6Orthoclase
  7. 7Quartz
  8. 8Topaz
  9. 9Corundum
  10. 10Diamond
Colour
Yellowish brown

Orange yellow

Tenacity
brittle
Fracture
Conchoidal
Density
2.08 g/cm³

Classification

Strunz
10th ed.

9.HC.25

  • 9SilicatesClass
  • 9.HUnclassified silicatesDivision
  • 9.HCWith Mn, FeGroup
  • 9.HC.25Aquacreptite (of Shepard)Species

Literature, links & citation

Citations
  1. 1868Shepard, C.U. (1868) On aquacreptite, a new mineral, and on corundophylite of Chester, Massachusetts. American Journal of Science, Series 2: 46: 256-257.
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Aquacreptite (of Shepard) — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/aquacreptite-of-shepard-287},
  note      = {Accessed 2026-05-11}
}