Citrine is a variety of quartz whose color ranges from a pale yellow to brown due to ferric impurities. Natural citrines are rare, and most commercial citrines are heat-treated amethysts or smoky quartzes.
Moonstone is a sodium potassium aluminum silicate. Its name is derived from a visual effect, or sheen, caused by light diffraction within a microstructure consisting of a regular succession of feldspar layers. It is composed of two feldspar species, orthoclase and albite.