Crystopedia
IMA mineral species

Sepiolite

Mg₄Si₆O₁₅(OH)₂·6H₂O

Soft and porous white magnesium silicate clay mineral.

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Sepiolite specimen
Sepiyolit.jpg · Wikimedia Commons (see file page for author & license)

Properties

Chemical formulaMg₄Si₆O₁₅(OH)₂·6H₂O
ElementsMg, Si, O, H
Crystal systemOrthorhombic
Mohs hardness2 – 2.5
Density—
Streakwhite
Color—
IMA symbolSep
Nickel–Strunz class9.EE.25

“—” means no reliable value in Wikidata yet. Check Mindat for full data.

🌍 Where it's found

Type locality (where it was first described): Bettolino, Italy

  • Type locality
  • Notable source / deposit
  • Country of origin

Marker positions are approximate (region or locality level). Type localities from Wikidata; notable sources curated by Crystopedia.

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