Mineral phase
- IMA name
- Clinoptilolite series
- Class
- silicate mineral
- Compound type
- tektosilicate
- Formula
- $(Na,Ca_{0.5},K)_{2-3}Al_3(Al,Si)_2.Si_{13}O_{36}\bullet12(H_2O)$
- Chemical formula
- (Na,K,Ca0.5})2-3Al3(Al,Si)2Si13O36•12(H2O)
- Elemental formula
- (Na)0-3 (Ca)0-1.5 (K)0-3 (Al)3-3.6 (Si)14.4-15 O48 H24
- Isotope mixture type
- terrestrial abundance
- Composition comments
- The cation content is highly variable. Ca-, Na-, and K- are dominant compositions but Sr, Ba, and Mg are in some cases substantial. Si/Al > 4.0. Fe and Mn can exist as impurities
- Oxides
-
Formula $Na_{2}O$ $K_{2}O$ $SrO$ $CaO$ $BaO$ $MgO$ $Al_{2}O_{3}$ $SiO_{2}$ $H_{2}O$ Mass fraction (%)
Strunz
- Class
- silicates (09)
- Division
- tektosilicate with zeolitic H2O (09.G)
- Family
- Chains of T10O20 Tetrahedra (09.GE)
- Code
- 09.GE.05
Dana
- Major class
- silicates (VIII)
- Class
- tectosilicate zeolite group (77)
- Type
- true zeolites (77.01)
- Group
- Heulandite and related species (77.01.04)
- Phase type
- crystalline
- Crystal system
- monoclinic
- Crystal class
- various
- Crystal class symbol
- various
- Crystal spacegroup
- various
- Comments
- Can be C2/m, C2, or Cm
- Molar mass
- 2703.72 - $g/mol$
- Density
- 2.1 - 2.2 $g/cm^3$
- State NTP
- solid
- Refringence type
- biaxial
- Refringence sign
- positive or negative
- Birefringence
- 0.0030-0.0060
- Refraction index $n_{\alpha}$
- 1.476-1.491
- Refraction index $n_{\beta}$
- 1.479-1.493
- Refraction index $n_{\gamma}$
- 1.479-1.497
- Dispersion V
- Dispersion r > v to r < v strong
- Pure color
- colorless
- Color
- Colorless, White, Reddish white, Red
- Diaphaneity
- transparent to translucent
- Luster
- vitreous