First, make your own electromagnetic wand. The size of the N52 Rare Earth Magnets needs to be a half-inch (12 mm) diameter by half-inch deep magnet. Magnets of this size can be applied to gems of various sizes, from tiny 2mm gems to large 60mm or larger gems. When keeping the same distance from the gem, the smaller N52 grade neodymium magnet shows a weak response, and such response may not match the response listed in the gem's susceptibility index. Larger N52 neodymium magnets show the same response, but these oversized magnets are troublesome and using them can be very dangerous.

Anyone can easily make a wand for testing gems. Neodymium magnets can be purchased online at very low prices. The standard size and strength for gemstone testing is a ½" x½" (12.7 mm) cylinder of grade N52. As a handle for the magnet, a 2-inch long hexagon head bolt (½ inch wide) from a hardware store will do.
To make the storage container more compact, use an empty plastic lipstick tube. The length of the lipstick tube is about the same as a medicine bottle (3 inches), but the diameter is much narrower, so it can be made into a slim magnetic cane carrying case. You may need narrower hex heads. Put a little foam rubber into the bottom of the test tube to cushion the magnetic field. Never let children reach it. At the same time, please do not put magnets on electronic devices such as calculators, mobile phones, tablets, PCs and desktop computers. People have different opinions on whether neodymium magnets will damage delicate circuits or erase memory, but it is recommended that you do not try. After all, it is known from experience that it can still erase the identification chip or identification strip on credit cards and hotel room key cards.
The 2'X 2'working area without metal objects is absolutely safe. Work surfaces made of wood or glass are safe, but metal surfaces such as filing cabinets and metal table tops must be avoided.
Unless you test first to make sure they are not ferromagnetic, be sure to keep other equipment (such as magnifiers, polarizers, beam splitters, refractometers, and microscopes) away from your work area. When you focus on testing, it is easy to forget the strength of the neodymium magnet. If the magnet is placed too close to the ferromagnetic precision instrument, the sudden impact will damage it. Most of the newer instruments are made of non-magnetic alloys and can be safely around your work area, but please use weaker magnets for careful inspection first.

Next, make a storage container. When not in use, strong magnets must be stored safely. The standard 3-inch long X 1 1/8-inch wide plastic medicine bottle has a child-proof cap and can be made into a safe storage container for cylindrical magnets on the bolt handle. It is recommended to put a caution label on the container. A piece of putty or standard 1 1/8" gem pot foam can be placed on the bottom of the container as a support pad for the magnet to cushion the strong magnetic pull at the exposed bottom pole of the magnet. https://www.zhijiangmagnet.com