Hydrotalcite
Mineral Mg6Al2(CO3)(OH)16·4H2O
About it
Soft, white, greasy-feeling plates and twisted masses in serpentinite, much like brucite. First found at Snarum, Norway; it gave its name to a family of layered compounds made as antacids and catalysts.
- Type
- Mineral
- Group
- Carbonate, hydrotalcite group
- Formula
- Mg6Al2(CO3)(OH)16·4H2O
- Hardness (Mohs)
- 2
- Specific gravity
- 2–2.1
- Streak
- white
- Lustre
- pearly, waxy, greasy
- Crystal system
- Trigonal
- Colours
- white, colourless, pale brown
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect basal; flexible but not elastic plates, greasy feel
Typical values: real specimens vary. For more, see mindat.org.