These rather special  Lepidolite tumbled stones

are Medium size

Lepidolite tumbled stones , like other micas, has a layered structure of lithium aluminum silicate sheets weakly bonded together by layers of potassium ions.

These potassium ion layers produce the perfect cleavage. Lepidolite crystals accompany such other lithium bearing minerals such as tourmaline, amblygonite and spodumene and can add greatly to the value of these specimens.