A 3X eyeglass/jewelry loupe is a type of folding magnifier that is used to examine jewelry, stamps, coins and the like. It makes the object appear three times larger than normal.
Loupes come in different magnifications to meet the needs of both professionals and hobbyists. Jewelers use the 10X loupe to examine jewels for defects, color and clarity, while a coin collector uses a lower-magnification loupe.
Loupes are available with single lens or triple lens. The single lens model can distort or add colors to the piece being examined. The triple lens model uses three lenses simultaneously, helping to eliminate the distortion and adding of colors.