How to Use a Jeweler’s Loupe

Posted on April 11, 2019 by Mary Hood | 0 Comments

If you’re interested in repairing jewelry, becoming a jeweler, or collecting antique jewelry, you’ll need to have a jeweler’s loupe in your arsenal. The following are a few tips for choosing the right jeweler’s loupe for your needs—and then putting that loupe to use!

How to Use a Jeweler’s Loupe | Barbara Michelle Jacobs Blog

Finding the Right Loupe

There are three common varieties of loupe lens configurations.

Singlet: This is a single lens that serves as a magnifying glass. There may be some distortion in the magnification, but these are fairly inexpensive. Keep in mind that if you’re using a singlet to look at a particular point in a gem (like an inclusion), you will likely be able to focus only on that point; the surrounding area will be distorted.

Doublet: A doublet features two lenses glued together. It offers a clearer, sharper view than a singlet.

Triplet: Triplets are the industry standard. These include two concave lenses and one convex lens stacked together. Triplets offer an even clearer and shaper image. Of the three lens configurations, triplets present color most accurately. A clear view of a gem's color is integral in determining its value. A triplet is also the best option for viewing a gem with minimal distortion. (Keep in mind that any magnifying lens may distort subjects viewed through the perimeter of the lens).

The are three most common powers of magnification.

10x: This is the standard power for triplets. When using a loupe with a magnification of 10x, you can keep the loupe about one inch away from your eye. This gives you a pretty decent field of vision.

20x: A loupe with a magnification of 20x will need to be brought closer to your eye (about ½ inch), which decreases field of vision. A lens configuration with a power of 20x is more expensive to produce, so many loupe manufacturers will make 20x loupes smaller than 10x loupes. This means that the natural distortion around the edge of the lens will be closer to the center.

30x: Any challenges experienced with a 20x loupe will be experienced to a greater degrees when using a 30x loupe.

Other considerations:

Some loupes come with LED lights mounted around or beside the lens(es). Some also include diffusers to cut down any glare caused by the lights. This innovation in loupes can certainly come in handy if you’d appreciate a little more light when viewing small pieces.

How to Use a Jeweler’s Loupe | Barbara Michelle Jacobs Blog

A loupe with an LED light.

Using Your Loupe

Using a jeweler’s loupe may feel a bit counterintuitive at first. You don’t have to close one eye or squint when using the loupe. In fact, keep both eyes open to avoid eye strain and headache. You will, however, want to view the subject with your dominant eye.

With one hand, bring your loupe about one inch away from your dominant eye. You can rest your hand against your cheek for extra stability. With the opposite hand, bring your subject under the lens. For stability, you can rest your hands together.

Using a Jeweler's Loupe | Barbara Michelle Jacobs Blog