Rainbow Moonstone Crystals
Rainbow moonstone is a trade name for any type of feldspar that exhibits a flash of blue colour. Correctly known as schiller or adularescence, it's caused by the reflection and scattering of light.
Adularia which is a feldspar mineral is one of the most common materials labelled as rainbow moonstone.
Rainbow moonstone is a type of white labradorite.
These grade A rainbow moonstone tumbled stones come from stone mined in India. Some but not all exhibit schiller as they interact with light. Most tumbled stones produced in India are cut and polished by hand. These stones were produced in an industrial sized rock tumbler.
The black mineral inclusion is tourmaline.
Although classed as a medium sized tumbled stone size does vary from piece to piece.