Paraiba Topaz- No Mine Exists

June 6th, 2009 by James L. Sweaney, CGA, FGA. GG
Where is the mine?

So where is that mine?

I was recently asked to appraise this topaz and a matching pair of 8 mm triangles. At first glance, the stones had a sort of attractive somewhat muted “teal” greenish blue color but something about the look of the stones was not quite right. A quick examination under our trusty gemological microscope revealed a surface coating on the stones. You can see the “scummy” look on the facet surfaces in the following photos.

surface coating show in reflected light

The surface coating shows in reflected light

odd look on the surface of the facets

Note the odd look on the facet surfaces of the left stone

The colored coating has been applied to either colorless or regular old irradiated blue topaz to create a look similar to Paraiba tourmaline. The result isn’t as nearly as vivid or attractive as the real Paraiba material, and of course the colorless or blue topaz is very common and inexpensive.

Additionally, coatings like this are thin and rather fragile– likely to wear off or become damaged by repairs or repolishing. This photo shows the thin nature of the coating.

defect in coating on blue topaz, photo courtesy of John Koivula

A defect in the coating on a blue topaz, photo courtesy of John Koivula

It’s certainly not illegal or objectionable to sell coated or treated gem materials, but it is really treading the line between fraud and fair business practices to use a term like Paraiba to describe this very inexpensive and common topaz. In the legitimate gem trade, the word Paraiba describes a rare and very valuable type of “neon” blue or green copper bearing tourmaline, originally mined in the state of Paraiba in Brazil (see our earlier blog for a picture of a museum quality Paraiba tourmaline).

My client was not aware that her stones were coated, and I suspect she may have paid a pretty high price. She was disappointed when I told her that the value was similar to that of irradiated blue topaz.

A quick Google search revealed “Paraiba Topaz” available from many sources for very inexpensive prices. In some cases, it was described as “rare.” Ebay showed 73 results when we searched the term. All we can say is “buyer beware.”

Our mission as members of the American Gem Trade Association (AGTA) and the American Gem Society (AGS) is to educate our customers about gemstones and to fully disclose the nature and quality of our gems and jewelry. The Gemstone Information Manual, a detailed explanation of gem treatments is available free as a download from the AGTA website, http://www.agta.org/info/index.html.

We offer expert gemological identification and appraisal services six days a week, 10 am to 5:30 pm– Give us a call or come by the shop. Visit our Gallery of Gems to see fine gems with full grading reports, including full disclosure of origin (if known) and of treatment (if present).

Tags: , , ,

Other Posts

Comments are closed.

Member - American Gem Society Member - American Gem Trade Association Polygon - The Jewelers Information Highway Harmony Recycled Precious Metals Firemark Diamonds