A loupe is a type of hand-held magnifier that is used in many professions and hobbies. The evaluation of diamonds, gemstones, coins, stamps, comic books and cards are all done with the help of a loupe. Loupes come in different strengths of magnifications. From 3x up to 30x and higher. There are also different types of lenses used in a loupe. Those types are:

Doublet

A doublet is a loupe that is made up of two lenses placed together.

Triplet

A triplet is a loupe made up of 3 lenses. This is a higher quality loupe.

High-end loupes can have lenses that are corrected for both color and distortion.