Eudialyte
Mineral Na15Ca6Fe3Zr3Si(Si25O73)(O,OH,H2O)3(Cl,OH)2
About it
Raspberry-red to brownish grains and masses in nepheline syenite, with black aegirine and white feldspar; Kola Peninsula, Greenland, and Mont Saint-Hilaire, Quebec.
- Type
- Mineral
- Group
- Silicate (cyclosilicate), eudialyte group
- Formula
- Na15Ca6Fe3Zr3Si(Si25O73)(O,OH,H2O)3(Cl,OH)2
- Hardness (Mohs)
- 5–6
- Specific gravity
- 2.74–3.1
- Streak
- white
- Lustre
- vitreous (glassy), greasy
- Crystal system
- Trigonal
- Colours
- raspberry red, pink, red, brown, yellow
- Transparency
- transparent, translucent, opaque
- Cleavage and fracture
- indistinct; uneven fracture
Typical values: real specimens vary. For more, see mindat.org.