They're sparkly with varied hues. You might see them in a beautiful necklace, a breathtaking ring, or even in a computer. They're gems! Gems are some of Earth's most precious resources, and some of them are millions of years in the making. This detailed text, accompanied by colorful photographs, informs readers about the remarkable processes that take place under the surface of Earth to form different kinds of gems. They'll also learn how some gems are mined, while others are replicated in laboratories. Future lapidaries will also find out how they might find and polish gems for themselves.