Zinnwaldite

Template:Short description Template:Infobox mineral Zinnwaldite, KLiFeAl(AlSi₃)O₁₀(OH,F)₂, potassium lithium iron aluminium silicate hydroxide fluoride is a silicate mineral in the mica group. The IMA status is as a series between siderophyllite (KFe₂Al(Al₂Si₂)O₁₀(F,OH)₂) and polylithionite (KLi₂AlSi₄O₁₀(F,OH)₂) and not considered a valid mineral species.<ref name=Mindat/>

Name and discovery

It was first described in 1845 in Zinnwald/Cinvald (today Cínovec) on the German-Czech Republic border.<ref name=Mindat>Mindat</ref>

Occurrence

It occurs in greisens, pegmatite, and quartz veins often associated with tin ore deposits. It is commonly associated with topaz, cassiterite, wolframite, lepidolite, spodumene, beryl, tourmaline, and fluorite.<ref name=Handbook>Handbook of Mineralogy</ref>