If you’re interested in repairing jewellery, becoming a jeweller or collecting antique jewellery you’ll need to have a jeweller’s loupe in your workshop.
The following are a few tips for choosing the right jeweller’s loupe for your needs—and then putting that loupe to use!
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 and 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 sharper image. Of the three lens configurations, triplets present colour most accurately. A clear view of a gem’s colour is integral in determining its value. A triplet is also the best option for viewing a gem with minimal distortion.
These are the 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 2 cm 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 1.2 cm) 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 degree when using a 30x loupe.
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.
Using Your Loupe
Using a jeweller’s loupe may feel a bit counter intuitive 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 2 cm 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.