Constituent
Name
Mg-Fe-silicate glass with olivine stoichiometry, Fe content 0.6
Official name
Synthetic olivine group
Family
ionic solid
Class
mixed salt
Compound type
nesosilicate
Constituent abundance in material
Relevance
main - major
Arrangement
single phase
Mass fraction
1.0
Mole fraction
1.0
Chemical composition
Formula
(Mg$_{0.4}$Fe$_{0.6}$)$_2$SiO$_4$
Chemical formula
Mg0.8Fe1.2SiO4
Elemental formula
(Mg)0.8-2 Fe1.2 (Si)1-2 (O)4-8
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Mole fraction Isotope mole fraction State Relevance
$Mg$ Magnesium element 0.8 0.1142857142857143 1.0 constituent element main
$Fe$ Iron element 1.2 0.17142857142857143 1.0 constituent element main
$Si$ Silicon element 1 0.14285714285714285 1.0 constituent element main
$O$ Oxygen element 4 0.5714285714285714 1.0 constituent element main
Chemical bonds
  Bond Number
$\cdot Mg^{2+} \cdot O^{-}-$
$\cdot Fe^{2+} \cdot O^{-}-$
$\cdot (\cdot) Fe^{3+} \cdot O^{-}-$
$\cdot Ni^{2+} \cdot O^{-}-$
$\cdot Mn^{2+} \cdot O^{-}-$
Class
mixed salts (08)
Phase type
glassy
Crystal system
amorphous
Crystal class
N/A
Crystal class symbol
N/A
Crystal spacegroup
N/A
Comments
mostly orthorhombic system except 1 member. In Mindat the group also includes A=Ca^{2+}
Molar mass
140.69-351.71 $g/mol$
Refringence type
biaxial