loupe(n = noun.artifact) jeweler's loupe - small magnifying glass (usually set in an eyepiece) used by jewelers and horologists;
is a kind of hand glass, magnifying glass, simple microscope
Any of a variety of small magnifying glasses, having a magnifying power from 2X to 20X, commonly of 10X, which may be held in the hand, or in some cases held within the eyesocket without the use of a hand. It is commonly used by jewelers and watchmakers. [PJC]
loupe, n. a small magnifying glass used by jewellers etc.
Etymology:
F