Material Index
| Name | Formula | Classifications | Members | Image | Lines | Spectra | Techniques | Tags |
|---|---|---|---|---|---|---|---|---|
| Kirschsteinite | CaFeII(SiO4) | Olivine | — | 0 | 0 | — | Mineral, Silicate | |
| Klöchite | (FeIIFeIII)☐2KZn3(Si12O30) | Osumilite (group) | — | 0 | 0 | — | Mineral, Silicate | |
| Knorringite | Mg3Cr2(SiO4)3 | Garnet | — | 0 | 0 | — | Mineral, Silicate | |
| Kokchetavite | K(AlSi3O8) | Alkali feldspar | — | 0 | 0 | — | Mineral, Aluminosilicate | |
| Kosmochlor | NaCrIIISi2O6 | Clinopyroxene | — | 0 | 0 | — | Mineral, Silicate | |
| Kostylevite | K2ZrSi3O9·H2O | — | — | 0 | 0 | — | Hydrated , Mineral, Silicate | |
| Kratochvilite | C13H10 | — | — | 0 | 0 | — | Mineral, Duplicate , Organic | |
| Kratochvílite | (C6H4)2CH2 | — | — | 1 | 0 | — | Mineral, Organic | |
| Krut'aite | CuSe2 | Pyrite (group) | — | 0 | 0 | — | Mineral, Selenide | |
| Krypton | Kr | — | — | 6 | 0 | — | Element | |
| Kumdykolite | Na(AlSi3O8) | Feldspar (group) | — | 0 | 0 | — | Mineral, Aluminosilicate | |
| Kumtyubeite | Ca5(SiO4)2F2 | Chegemite (subgroup) | — | 0 | 0 | — | Mineral, Silicate , Halide | |
| Kunzite | LiAlSi2O6 | Spodumene | — | 2 | 1 | CL/SEM | Variety, Silicate | |
| Kurchatovite | CaMgB2O5 | — | — | 3 | 0 | — | Mineral, Borate | |
| Kushiroite | CaAlAlSiO6 | Clinopyroxene | — | 0 | 0 | — | Mineral, Aluminosilicate |
