Constituent
Name
magnesian Nyerereite
IMA name
Nyerereite
Class
non-silicate mineral
Compound type
carbonate
Chemical composition
Formula
Na1.5-1.9K0.05-0.4(Ca)0.8-1CO3
Chemical formula
(Na,K)2Ca(CO3)2
Elemental formula
(Na+)1.5-1.9 (Ca2+)0.8-1 (K+)0.05-0.4 (Sr2+)0-0.05 (C)1.9-2 (O-)5.7-6.52 (S)0-0.1 (P)0-0.03
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
Na⁺ Sodium cation element 1.5 - 1.9 1.0 constituent cation main
Ca2+ Calcium cation element 0.8 - 1 1.0 constituent cation main
K⁺ Potassium(1+) cation element 0.05 - 0.4 1.0 constituent cation substituted
Sr2+ Strontium cation element 0 - 0.05 1.0 constituent cation substituted
(CO3)2- Carbonate anion chemical function 1.9 - 2 1.0 anionic radical main
(SO4)2- Sulfate anion chemical function 0 - 0.1 1.0 anionic radical substituted
(PO4)3- Phosphate anion chemical function 0 - 0.03 1.0 anionic radical substituted
Composition comments
may also have large number of vacancies (up to 0.2) contain small amount of Ba(1-3%), F and Cl (~2%)
Chemical functions
  Function Number
(CO3)2- 2
Chemical bonds
  Bond Number
· Ca2+ · O-- 2
……C…O-2/3 3
Na⁺ · O-- 2
Oxides
Formula Na2O CaO K2O SrO CO2 SO3 P2O5
Mass fraction (%)
Oxides comments
and also possibly BaO, F and Cl

Strunz

Class
carbonates - nitrates (05)
Division
carbonates without additional anions, without H2O (05.A)
Family
Alkali and alkali-earth carbonates (05.AC)
Code
05.AC.10

Dana

Major class
carbonates, nitrates, borates (V)
Class
anhydrous carbonates (14)
Type
with Compound Formula A+2B++(CO3)2 (14.03)
Group
-Nyerereite- group (14.03.04)
Code
14.03.04.01
Phase type
crystalline
Crystal system
orthorhombic
Crystal class
dipyramidal
Crystal class symbol
mmm (D2h)
Crystal spacegroup
Pbca
Comments
initialy assumed to have Cmc2(1) space group
Molar mass
206.08 g/mol
Density
2.541 g/cm3
Refringence type
biaxial
Refringence sign
negative
Birefringence
0.0230
Refraction index nα
1.511
Refraction index nβ
1.533
Refraction index nγ
1.534
Color
colorless
Diaphaneity
transparent