Noun
a precious or semiprecious stone incorporated into a piece of jewelry
Source: WordNetPliny is presenting an archaic view, as in his time amber was a precious stone brought from the Baltic at great expense, but the Germans, he says, use it for firewood, according to Pytheas. Source: Internet
However, Thorin turns on the Hobbit as a traitor, disregarding all the promises and "at your services" he had previously bestowed. citation In the end Bilbo gives up the precious stone and most of his share of the treasure to help those in greater need. Source: Internet
This precious stone set in the silver sea, Which serves it in the office of a wall Or as a moat defensive to a house, Against the envy of less happier lands. Source: Internet
Up to the discoveries of bulk amethyst in Brazil in the 19th century, amethyst was considered a precious stone as well, going back to ancient Greece. Source: Internet