- I
-
- Icosahedral
- Icosahedron
- Icosi-tetrahedron
- Idiochromatic
- Igneous
- Igneous rock
- Impure
- Impurity
- Inclusion
- Incrust
- Incrustation (pseudomorph)
- Incrustation (crust)
- Incrusting
- Index of refraction
- Indiscernible
- Infiltration
- Inosilicates (subgroup)
- Inorganic
- Intaglio
- Insoluble
- Intermediary
- Intrusive rock
- Ion
- Iridesce
- Iridescence
- Iridescent
- Irradiation
- Isometric (crystal system)
- Isomorph
- Isomorphous
- Isomorphism
- Isotropic
- Isotropization
- Isotype
- Isotypous
- Isotypism
- Ivory