IPA: /ˈdʒɛmˌstoʊn/
KK: /ˈdʒɛmˌstoʊn/
A valuable stone that is often cut and polished to be used in jewelry or as decoration.
She wore a beautiful necklace with a large gemstone in the center.
Gemstone → It is formed from "gem" (from Old French *gemme*, meaning precious stone) and "stone" (from Old English *stan*, meaning rock or stone). The word "gemstone" refers to a precious stone or a valuable mineral that is cut and polished for use in jewelry.
Think of a 'precious stone' ('gem') combined with 'rock' ('stone') — that's what a gemstone is, a valuable stone.