Questions About Gems and Jewelry

Basic common questions about gems and jewelry.

Questions About Gems and Jewelry

  • “Sphalerite Cut” by Eurico Zimbres is licensed under CC By-SA 3.0
    Sphalerite Appraisal

    Question I’ve come across what I believe is an unusual specimen and I’m looking for someone to help me come up with an approximate value for this. I’ve got a brilliant cut sphalerite that is 11.5 ct and 13mm across. It’s a brilliant…

  • “Faceted Diamond 1” by James St. John is licensed under CC By 2.0
    What Is A Reflectometer?

    Question In my quest for a refractometer, someone suggested that I purchase a reflectometer as a more affordable alternative. However, I’m having difficulty getting much information on this tool as it relates to gemstones. Do you know anything…

  • “Opal Necklace” by James Petts is licensed under CC By-SA 2.0
    Opal Jewelry Tips

    Question I was a bit disappointed with your description of opal wearability as “Poor.” Bit harsh I think. If it’s worn as a ring I could understand the comment, but how about brooches and pendants? Not too much abrasive action on stones in…

  • “Rhodolite Garnet.” Rob Lavinsky, Used with permission.
    What Is A Rhodolite Gem?

    Question I recently bought a rhodolite. It’s clean and has a beautiful dark red color. My problem is simply that I’m wondering if it’s truly rhodolite or some other type of garnet. This is the first time I’ve purchased this garnet…

  • “Chrysoprase inlay rings in sterling and 14k gold. Carved, cast, and inlay all done in-house by Mark Anderson” by Jessa and Mark Anderson is licensed under CC By 2.0
    Does Chrysoprase Jewelry Fade?

    Question From different sources, I’ve heard that chrysoprase fades in sunlight or heat. How sensitive is it? Does normal daytime wear affect the stone color? Should chrysoprase be worn mostly at night to preserve its vivid color? Can the color…

  • “Yellow Topaz Ring” by Mark Somma is licensed under CC By 2.0
    Why Are Topaz and Citrine Gemstones Misidentified?

    Question Could you explain the difference between topaz and citrine gemstones? I recently had appraised what I believed to be a 1-carat topaz. When I bought the gem 18 years ago, the jeweler appraised it as a topaz. Now, the new appraisal says…

  • “Diamond on Blue” by Koshy Koshy is licensed under CC By 2.0
    Wearing Gemstones That Touch Your Ring Finger For Health

    Question What’s the best way of wearing gemstones most suited to me in terms of health? I want to create a wedding ring for myself with a setting in which the stones are actually touching my skin. Is there any wisdom on this you can share with…

  • “Swarovski Earrings Blue Zircon Silver with Prongs” by Maria Panayiotou is licensed under CC By-ND 2.0
    Gemstone Colors And Identification

    Question I’m getting started in gemology but I think I have a bad problem. I’m red, green, and brown colorblind. I see and enjoy colors but I don’t know what colors I’m looking at. I love faceting stones and have recently completed a new…

  • Emeralds and peridots can coexist, if you carefully compare their colors side by side before purchasing.  “Green Grapes – Emerald and Peridot Briolette Cluster Earrings” by Natalia Photos is licensed under CC By-SA 2.0
    Do Emeralds and Peridots Look Good Together?

    Question Do you think emeralds and peridots can be combined in jewelry? I’m interested in designing a unique engagement ring.  I want it to feature my and my fiancé’s birthstones as accents to a diamond center stone. Mine is emerald.  His…

  • “Гелиодор, Шерловая Гора, Россия (Heliodor, Sherlovaya Gora, Russia)” by Smallru is licensed under CC By-SA 4.0
    Is Golden Beryl A Good Gem Choice For Jewelry?

    Question I want to know more about golden beryl. Is it rare? What is its wholesale and resale value? Is it a good stone for jewelry? Answer Golden beryl is also called heliodor, which is Greek for “gift of the sun.” This gem’s value depends…

  • Natural alexandrite is very rare and quite stunning.  These factors help create a market for synthetic alexandrite as an option for jewelry.  Synthetic alexandrite is real alexandrite created in a lab.  “55.88 ct Synthetic Alexandrite.” © All That Glitters. Used with permission.
    Is Synthetic Alexandrite Real Alexandrite?

    Question What are the chances that the stone in my 40+ year-old ring is a real alexandrite? It changes color from blue to a deep purple. The gem is emerald cut and it’s in a very pretty setting. The ring was a gift for my June…

  • Opals are very sensitive to sudden changes in temperature.  If you purchase opals that have been stored in water, you'll need to dry them slowly.  They may crack if they're dried too quickly.  “Rough Opal” by Deidre Wollard is licensed under CC By 2.0
    How To Dry Opals Safely

    Question I happened upon some opal in the raw when I was traveling in Honduras. There were ten pieces in a bottle filled with water. The man who sold them to me said I needed to keep them underwater. I’d like to have the opals shaped and polished…

  • “Brazilian Agate” by David Lofink is licensed under CC By 2.0
    Where Can You Find Agate Stones Forming?

    Question I’m fascinated by agate, especially the kind found in basaltic or other lava cavities.  The stones from Botswana and Brazil are my favorites.  These were formed at some time in the remote past. After the lava had hardened, water…

  • “Chameleon Pear Shape Diamond by Leibish & Co.” by Fancy Diamonds is licensed under CC By 2.0
    What Is A Chameleon Diamond?

    Question Recently someone offered me a chameleon diamond that changed shades from yellow/green to yellow. She tried to convince me that it was different than a color change gemstone. I didn’t know enough to argue. Can anyone expand on…

  • “Beryl var. Emerald” by Géry Parent is licensed under CC By-ND 2.0
    What Causes Emerald Fractures?

    Question Aquamarine and most other members of the beryl family have nice big, clean crystals. Why are emeralds different in general? What causes emerald fractures? No one has given me a good answer yet. Isn’t a beryl a…

  • Polishing silver can be time consuming.  Polishing silver jewelry presents additional challenges, especially when dealing with gemstone pieces with tarnished silver. “Julia Polishes” by is licensed under CC By-ND 2.0
    Recommendations For Polishing Silver Jewelry

    Question I have some questions about polishing silver jewelry. I’ve tried a number of methods that work well, but none are particularly easy. I’d love to hear some suggestions for making polishing silver easier. I was also wondering if anyone has…

  • Goshenite and aquamarine are both varieties of beryl.  White or colorless beryl is called goshenite.  If a beryl gemstone has iron traces, it shows a blue to blue-green color.  In that case, it is called an aquamarine.  So-called white aquamarines are not aquamarines at all.  Most likely they are goshenite gemstones mislabeled in error or deliberately.  “Beryl (Var: Goshenite).” © Rob Lavinsky, Used with permission.
    Are White Aquamarines Genuine Aquamarines?

    Question A friend of mine showed me some gems he claimed were white aquamarines. I told him those were not aquamarines, but he insists they are. Supposedly he got a good deal on them because they are colorless instead of blue. Is there actually…

  • Credit: NASA/Goddard Space Flight Center/Bill Hrybyk

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    The Pocket Spectroscope: A Quick Guide For Gemologists

    Question My granddad was a gemologist. When he passed away 10 years ago, I inherited many of his things, including lots of gemological instruments. One of these is a mystery to me. It’s a small instrument about 5 cm in length. It has a sticker…

  • A lab-created emerald is a real emerald but not a natural emerald.  Synthetic emeralds are some of the most expensive synthetic gems.  The energy-intensive methods used to create them in labs require expensive equipment.  The process is slow, and the yield of facetable material is low.  Nevertheless, a lab-created emerald is not nearly as valuable as a natural emerald.  “Synthetic Emerald” by Deidre Woollard is licensed under CC By 2.0. (Cropped to show detail).
    Is A Lab-Created Emerald A Real Emerald?

    Question I want to get an emerald pendant for a Christmas present. I’ve talked to some jewelers who are trying to push lab-created emerald pieces. I’ve been told synthetic emeralds are just like the genuine stones. They also say synthetics are…

  • Custom-cut gemstones don't fit into the mass production process.  However, they can fit into unique jewelry designs.  This hand-made platinum ring features a 2.56 ct. center diamond and custom-cut, very thin, tapering baguette diamonds only 8mm long on each side.  “Special diamonds...” by gemteck1 is licensed under CC By 2.0
    Price And Value: Factory Cut Vs. Custom-Cut Gemstones

    Question I’m confused about the effect of faceting on a gem’s value. Specifically, what’s the difference in value between factory-cut and custom-cut gemstones? Is that something you can calculate? I was recently told that the majority of my gems…

  • “Kammererite.” © Rob Lavinsky, Used with permission.
    An Introduction To Turkey’s Gemstones

    Question I’m a novice gemology student. I’m traveling to Turkey in the near future and I’d love to know more about Turkey’s gemstones. What might I find on my visit? I’ve got my gem identification book ready to go. Any information would be…

  • “Aaron by Giovanni Maria Morlaiter” by Wolfgang Moroder is licensed under CC By-SA 3.0. (Cropped to show detail).
    What Were The Gemstones Of The Breastplate of Aaron?

    Question I’d love to have some feedback on the identity of the gemstones of the breastplate of Aaron. In Exodus 28:15-21, the breastplate of Aaron is described in great detail. In the Tanakh, the Hebrew Bible, a different gemstone is listed for…

  • “Mozarkite,” the state stone of Missouri, by Astynax. Public Domain.
    What Is The Difference Between Chert, Flint, And Mozarkite?

    Question I’m a little confused about chert and flint. In your gemstone listing entry on quartz, you identify both chert and flint as examples of cryptocrystalline quartz. They are described together as “opaque, dull gray, or whitish chalcedony,…

  • “Velvet Beauty,” Tucson Gem and Mineral Show 2007, by cobalt123 is licensed under CC By-SA 2.0
    Reviews of The Tucson Gem and Mineral Show

    Novice and expert gemologists discuss their experiences at the celebrated annual February Tucson Gem and Mineral Show. You’ll find reviews of shows from 2002 to the present.

  • “Uranium Glass” by UCL News is licensed under CC By-ND 2.0
    Is Uranium Glass Safe To Facet?

    Question A friend of mine was going through some old stuff in his attic and found something labelled “atomic glass.” Since it looked like a yellow gem, he gave it to me. (By the way, it’s preformed to a nice, big emerald cut). Any ideas what…

  • Spencer, Idaho, is the source of very rare and beautiful star opals.  “05212008333,” Spencer, Idaho, by andresmh is licensed under CC By-SA 2.0
    Pricing Information For Star Opals From Spencer, Idaho

    Question I love working with opal from Spencer, Idaho. On rare occasions, I turn up a star stone. I know star opals are very rare. So as you can imagine, I’m having a heck of a time trying to put a realistic value on what I cut. Does anyone have…

  • “Serengeti Sunset,” Serengeti National Park, by Anita Ritenour is licensed under CC By 2.0
    Are Serengeti Rubies Real Rubies?

    Question Has anyone ever heard of Serengeti rubies? We bought two. The seller told us they were new to the US. Each is about 1 carat and a 7×5.3 mm oval. These stones are very clean and pink/purple in color. How rare are Serengeti rubies and…

  • “Mkushi_IMG_4279,” Tourmaline with Usambara effect; Chiblua mine; Mkushi area. © Leo Klemm,  Used with permission.
    What Is The Usambara Effect In Gemstones?

    Question I’m an engineering geologist mainly involved in tunnel construction. I also collect gemstones. My special interest is in color-change minerals. I’ve been involved in studies of a special color-change phenomenon, the Usambara effect. I’m…

  • “Indian rubies” by Mauro Cateb is licensed under CC By 2.0
    Should I Make An Investment In Bargain Rubies?

    Question Help me! I’ve been offered some rubies at a fabulous price but I’m scared to buy them. Why? There is a lot of money involved. (At least it’s a lot for me). This dealer has a package of large rubies, mostly 1 to 3 carats. They have lots…

  • “Ruby (fluorescent),” Jegdalek, Saroby, Afghanistan.  © Rob Lavinsky, Used with permission.
    Do Natural Rubies Fluoresce?

    Question I was told years ago that natural rubies fluoresce but lab-grown rubies will not. Recently someone told me the opposite. He says that synthetic rubies fluoresce but natural stones won’t. Can you settle this? Ken Answer All rubies…

  • Diamonds can be found in rocks like kimberlite, which form as magma cools.  These highly-prized gemstones may originate deep underground in extreme temperatures, but under what conditions can diamonds burn? “Diamond in Kimberlite 3” by James St. John is licensed under CC By 2.0
    Can Diamonds Burn?

    Question I came across this statement and was wondering if anyone can verify it: “A diamond is the hardest natural substance on earth, but if it is placed in an oven and the temperature is raised to about 763º Celsius (1405º Fahrenheit), it…

  • “5-carat Ruby Engagement/Wedding Ring” by 3BL Media is licensed under CC By 2.0
    Gemstone Wholesale Prices And The Art Of Appraising

    Question I’m having some emerald gemstones appraised by a Master Gemologist. Since I’m looking at selling the items I’m dealing in wholesale, do you know where I can find a list of gemstone wholesale prices? I want to familiarize myself with the…

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