© Kirk Feral 2009, All Rights Reserved. These materials may be duplicated for educational purposes only. No part of this website may be duplicated or distributed for profit, for commercial purposes, or for posting to another website, without the expressed written consent of the copyright holder.
The intent of this website is to introduce the magnetic wand and testing method to gem hobbyists and gem professionals, and demonstrate how enjoyable, rewarding...and effective... magnetic testing can be. The information in this website can be used as supplemental course material for introductory gem identification classes. Gem ID course instructors and students may freely print and duplicate the materials copyrighted by this author.
The reference charts and research results provided in this website have not been published elsewhere. These materials were developed entirely by this author/researcher using results of magnetic testing on private gem collections. The Magnetic Susceptibility Index is the only published index that provides both qualitative and quantitative measurements of the magnetic susceptibilities of most gemstones.
The idea of using a hand-held magnet as a gem identification tool is not new. Renowned British gemologist Basil Anderson proposed it in 1953. More recently, a few researchers have published information about using strong rare-earth magnets for gem testing (see Resources and Links). But for the most part, the practical value of magnetic testing has been overlooked or dramatically underestimated. As of 2013, the magnetic wand remains unknown to most gemologists, students, collectors, jewelers, and gem dealers.
This website provides information to help you get started using this tool, including: 1) an overview of magnetism in gemstones 2) how to use a magnet for gem identification, and where to buy magnets 3) an index of magnetic responses for over 250 gemstone species and color varieties, and 4) a reference chart for separating look-alike gems. Individual sections about Diamonds, Tourmalines and Garnets provide an in-depth look at the magnetic properties of these gems and how to identify them using a magnet.
If you collect, sell, or work with gems and need to know how to identify them, a magnet belongs in your set of standard testing tools, alongside your loupe, refractometer, polariscope and spectroscope. Once you start working with a magnet, you'll find it quickly becomes an essential part of your testing routine for all colored stones, as well as Diamonds.
A magnetic wand made with rare-earth materials is one of the most useful, and least known, tools for basic gem identification. An extremely sensitive instrument, it can be used to detect very slight magnetism in gems. It is small and portable, and simple to use. Unlike many other gemology tools, magnets are accessible to everyone. Wands can be easily assembled for just a few dollars.
3 Examples of Magnetic Responses
How is it Useful?
The Forgotten Tool
"Magnetic testing as Feral describes should be in the tool kit of all practicing gemologists."
Dr. D. B. Hoover FGA
Among its multiple uses, a magnetic wand provides the quickest means for identifying Garnet. Differences in magnetic response can often be used to distinguish natural gems from synthetics and imitations. For example, natural blue Spinel can in most cases be distinguished from synthetic blue Spinel, and natural Diamonds can often be separated from lab-created Diamonds. A magnet can be used to separate many types of gems that look alike, such as Aquamarine (Beryl) from blue Topaz, or Chrome Tourmaline from all other green Tourmalines of similar color. And magnetic testing can serve as an important method to corroborate the test results of your other gemology tools. Many more uses are presented on the page titled 10 Practical Uses for Gem Identification.
Magnetism in Gemstones
An Effective Tool and Method for Gem Identification
© Kirk Feral 2009
Magnetism is a measurable physical property of minerals. The study of magnetic properties is a long-established discipline of geology and mineralogy, but not of gemology. The method of testing described in this website is missing from the curriculum of gemology classes taught by gemology institutes, universities and gem & mineral societies. Research on this method is scarce, and information on the practical applications of gemstone magnetism for colored stones is almost non-existent in books, journals, and online. Notation of the magnetic properties of gemstones is conspicuously absent from nearly all compendiums and indexes of gems.