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How to do test 4?


Hi,ive looked through the syllabus,and i can’t find any articles saying the steps to take to examine and identify gemstones,only articles on using each piece of equipment for identification purposes.I presume that for test 4,i use my eyes first,then the microscope,then refractometer etc.How did others here go about test 4?im getting a bit overwhelmed with all the articles ive read,and am struggling to put it all together into a methodology for conducting test 4,ie how i go about identifying the gemstones.Also,did others find the gemmology tools download useful?


The syllabus articles, “An Introduction to Gem Identification,” and “The Art and Science of Identifying Gemstones” (in more detail), both discuss sequences for test procedures to narrow the possible gem IDs.


There really is no one definitive procedure. I recently completed IGS Certification. In some instances you may be able to identify the stone using one or two tests. In others, you may have run through every possible lab test you can and still be scratching your head. My process my be different than other peoples sequence. Start with the basics, color, inclusion types, S.G. Those 3 can tell you a lot about the stone. If that isn’t enough, move on to more tests… dichroscope and the others. Or perhaps do every test in your lab and note every result and observation. Its just a process of deduction. Narrowing it down and eliminating other possibilities until you can get it down to one possibility.