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CSI Gemology Part 2

Gemology can be a fascinating case of “who dunnit!” Trained Gemologist have a set of procedures and tests using general observation, equipment, and experience, similar to a crime scene detective, to determine what the gemstone in front of them is. Last week, I talked about the sometimes overlooked but important first step of general observation, , and this week, I want to talk about one of my favorite tools, the microscope!

Using a microscope is a little like general observation on steroids because you can see so many details hidden to the naked eye. Gemologist will grade gemstones at 10x, but we can observe them at higher powers making teeny-tiny details stand out. My microscope has a doubler lens which gives me option of looking at 90x!! So, what are the things a Gemologist is looking for underneath a microscope to help identify what the gemstone is?

· Inclusions: Inclusions are defined as internal characteristics of a gemstone, and interestingly, certain gemstones because of their chemical and crystal make-up will display inclusions that are unique to only them. For instance, Demantoid Garnet (a green variety of Garnet) has an inclusion that looks like a horse’s tail. Corundum (Sapphire, Fancy Sapphire, & Ruby) have inclusions that are not quite unique to them but are typical displayed, like needles or fingerprints.

· Gas Bubbles: Gas bubbles occur in imitation gemstones made of glass or plastic. For the most part, a mineral inclusion will be angular, but a gas bubble is round (and kind of looks like a doughnut) which is a quick way to determine what it is.

· Assembly: Assembled stones are two or more separate materials glued or fused together making it look like something it is not. A Garnet and Glass Doublet is made up of mostly glass with a thin layer of Garnet on top. This can mask as an incredible Ruby or Garnet.

· Doubling: A gemstone is either singly refractive or doubly refractive. You can see that by looking at the reflection of a facet line under the microscope where a singly refractive gemstone will reflect one line and doubly refractive gemstone will reflect two lines! Moissanite is doubly refractive while a diamond is singly refractive making it easy to cross diamond off the list if you see two lines reflected back!

I can go on for pages talking about all the things to look for underneath a microscope! As a Graduate Gemologist, my microscope has become one of my favorite tools because you can get up close and personal with a gemstone. I may or may not have named my microscope Scopey Blue Eyes!

I would love to help you with your special purchase or custom design! Angela Cisneros Jewelry Concierge brings back the joy and confidence of jewelry shopping, so that you can celebrate with ease! My by-appointment approach means:

  • One-on-one appointments (personal attention and no crowds!)

  • Discretion and privacy (surprises remain surprises!)

  • Expert help from a Graduate Gemologist with 23 years of experience (yep, that’s me!)

Book your FREE appointment with me today!

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