Minerals in space group 8

Lepidolite is the common name for a lilac-gray or rose-colored series of minerals in the mica group. The mineralogical name for this series is the polylithionite-trilithionite series. Lepidolite has a chemical formula of . It is the most abundant lithium-bearing mineral and is a secondary source of this metal. It is also the major source of the alkali metal rubidium, which substitutes (as in all minerals) for potassium.

Chapmanite is a rare silicate mineral belonging to the phyllosilicate group, discovered in 1924, and named in honour of the late Edward John Chapman (1821–1904), a geology professor at the University of Toronto. Chemically, it is an iron antimony silicate, closely related to bismutoferrite, and may contain aluminium impurities. It is closely associated with silver mines, most notably the Keeley mine in Ontario, Canada, found in quartz veinlets containing graphite in gneiss. It takes the form of a powdery, yellow-green, semitransparent solid, and leaves a streak of the same color. Early German

Fraipontite is a zinc aluminium silicate mineral with a formula of .

Caryopilite (synonymous with ectropite and ektropite) is a brown-colored mineral with formula (Mn2+,Mg)3Si2O5(OH)4. The mineral was discovered in 1889 from a mine in Sweden. It was named for the Greek words for walnut and felt in reference to its appearance.

Greenalite is a mineral in the kaolinite-serpentine group with the chemical composition (Fe2+,Fe3+)2-3Si2O5(OH)4.

Alsakharovite-Zn (IMA symbol: Ask-Zn) is an extremely rare alkaline strontium zinc titanium silicate mineral from the cyclosilicates class, with the chemical formula , from alkaline pegmatites. It belongs to the labuntsovite group.