Cultured pearls are composed of nacre, the same organic gemstone material as natural pearls. The fine jewelry industry's classification of them as precious gemstones reflects that material reality.
Care & Keeping
Fine jewelry earring posts are manufactured to consistent gauge standards, which is what makes universal clutch back sizing viable. The internal grip of a standard clutch back is sized to accommodate that gauge range, and comfort backs use the same post gauge range with a larger grip body for heavier earring formats.
Style Notes
If she already has multiple piercings and tends to layer her jewelry: stacking hoops with studs and other hoops is a popular practice. A single piece can upgrade the whole look.