Low power stereo binocular microscopes are a handy cross between a magnifying glass and a high power microscope. Looking through the two eyepieces, you can see items in 3D and move them around underneath the lenses, but with the higher magnification of a microscope. This is useful in a number of hobbies as well as scientific pursuits.

Dissecting

Stereo binocular microscopes -- with a lens at the top and bottom of each eyepiece -- were developed in biology labs to enable students and scientists to observe (and dissect) small creatures in three dimensions. Whereas the usual monocular compound microscope allows you to see items several 100s of times larger, you are restricted to a flat section on a slide. The low power stereo microscope with two eyepiece tubes trades much less magnification (10 or 20 times is typical) for the ability to maneuver a specimen in a wider, deeper field of vision than a high power scope.

Watchmaking

The magnification of a low power stereo scope is still much more powerful than a magnifying glass. A stereo microscope has a larger "stage" (where an object is placed for microscopic examination) than a typical compound microscope. This larger stage and higher power allows watchmakers room to manipulate tiny pieces with ease.

Gem identification

Gemologists quickly discovered the uses of a binocular stereo scope, allowing them to increase the power of magnification while retaining the ability to maneuver a stone and view it from all angles. Gemology binocular scopes tend to have specialized light sources useful for detecting flaws and identifying characteristics in stones.

Handling Small Parts

Any hobby or trade that requires you to see tiny details -- such as cancellation marks or feather arrangement -- and to manipulate small objects to see them from any angle could benefit from a binocular stereo microscope.

Discovering the Small World

Microscopes open a new world to children. Low power stereo binocular scopes are easier for newbies to look through than high power compound scopes, yet they provide enough magnification to reveal a small, unknown world. They are the only type of microscope that allows viewing an object without specially preparing the object.

Source:

Microscope Terms

Stereo Microscopes

Microscopes for Gemology

Resource:

How to Select a Microscope, by Mol Smith