Learning Center What is a mineral?The most common minerals on earth Information for Educators Mindat Articles The Elements The Rock H. Currier Digital Library Geologic Time

Minerals by Properties Minerals by Chemistry Advanced Locality Search Random Mineral Random Locality Search by minID Localities Near Me Search Articles Search Glossary More Search Options

The Mindat Manual Add a New Photo Rate Photos Locality Edit Report Coordinate Completion Report Add Glossary Item

Mining Companies Statistics Users Mineral Museums Clubs & Organizations Mineral Shows & Events The Mindat Directory Device Settings The Mineral Quiz

Photo Search Photo Galleries Search by Color New Photos Today New Photos Yesterday Members' Photo Galleries Past Photo of the Day Gallery Photography

Discussions

💬 Home 🔎 Search 📅 Latest

╳Discussions

💬 Home 🔎 Search 📅 Latest

Groups

Recent Images in Discussions

Fakes & Fraudsprobable clarity enhancement of quartz, rutile quartz and dumortierite quartz from china!

21st Feb 2016 13:56 UTCAlexander Ringel

There are more and more unusual crystal clear and transparent and unusual cheap rutile quartz specimen from china on the market. Also other specimens of quartz with incusions are usually only from china in top quality available. One example is the dumorttierite in quartz, wich seems to be only brilliant blue and absolutely perfectly clear without any crack when it is sold by chinese traders. And also other quartz samples are often uncommon cheap and clear. The remaining clouds and inclusions look unnatural. I guess, the chinese use widely a method to enhance the clarity of these specimens. So i want to ask, what the others think or heared about?

21st Feb 2016 15:03 UTCcascaillou

Here's some data about quartz treatments:

http://www.mindat.org/mesg-62-369000.html

However, if you're refering to pictures from the web, then you cannot rule out the possibility of simple picture manipulation (i.e. manipulating the colors and contrast of the picture with photoshop).

22nd Feb 2016 12:46 UTCAlexander Ringel

Actually im talking about samples, which appear on ebay (com) since about a year and become more and more and will due reselling probably come in every market very soon. Especially the dumorthirite quart and rutile quartz samples could be interesting objects for dealers in the middle and upper price range, if they are not aware about the risk of getting "improved" specimen. Judging from background and visible hands these pictures are not manipulated enough to explain the mentioned intense blue of dumortierite.

I think, the intensification of this blue and the improvement of the clarity are caused by the same method. I think it could be some kind of heat or hydrothermal high pressure treatment to heal the cracks.

22nd Feb 2016 15:43 UTCcascaillou

Judging from background and visible hands these pictures are not manipulated enough to explain the mentioned intense blue of dumortierite.

professional graphic softwares feature intelligent outline tools, which make it easy to modify the color/clarity/contrast of a few details without altering the the full picture.

22nd Feb 2016 20:22 UTCMilan Lidmera

Coincidentally, last week, I bought a small sample dumortierite on ebay , so how it will come , I will give knowledge on how it is in reality.

Milan

23rd Feb 2016 00:23 UTCKelly Nash 🌟 Expert

Wow, there are hundreds of those dumortierite-included quartz crystals (if that's what they are) on ebay, and many are quite spectacular looking. There are a couple of similar ones from Bahia, Brazil, here on Mindat. But these ebay crystals from China are pretty uniformly transparent and colorful. Nearly all of the crystals appear to have polished faces. Nowhere is there a specific locality mentioned, as far as I can tell.

23rd Feb 2016 01:46 UTCLawrie Berthelsen (2)

The case of the dumortierite in quartz was discussed in a previous topic, about 6 months ago, if I remember correctly.

I bought one on Ebay, and was disappointed to find that the blue in the photo had been considerably enhanced. The actual colour of the stone was more of a blue-grey, and yes, the crystal had been polished. The Chinese seller had the stone listed as being from Brazil. I have never seen a Chinese seller intimating that these stones are from China.

I did find one Brazilian seller in one of the satellite shows at Tucson this year with the rough material. It was very unspectacular looking, and very expensive, priced by the gram. I did not find a single piece that could be regarded as a desirable mineral specimen, either natural or if it was polished.

I suspect that Chinese buyers must have cornered the market in this material some time ago.

Buyer beware.

23rd Feb 2016 03:14 UTCGreg Dainty

I obtained one, the color was accurate and there has been no polished done to the specimen. actually its very nice.

3rd Mar 2016 21:06 UTCVernon

You have to be very careful about anything from China or Thailand. They make fakes of almost anything quartz included. Sometimes it may be real, but highly irradiated. Often times though it is just glass. Green included quartz is very rare. Some of the listings on ebay from China even say green grass included quartz. What they are likely doing is just putting green particle or grass inside glass. They will not advertise usually that something is fake. They want your money. So if it's cheap and seems to good to be true it likely is.

3rd Mar 2016 21:25 UTCAlfredo Petrov Manager

Ummmm... How do you put grass inside glass?

3rd Mar 2016 21:35 UTCVernon

It just looks similar in color to grass. Their English is poor so some of the titles are odd. For this example the title was "full natural grass green tourmaline rutilated quartz crystal rough diamond 345g" If you look at it you can see air bubbles indicating it is likely glass, with inclusions added in.

3rd Mar 2016 21:55 UTCAlfredo Petrov Manager

The description is wackily inaccurate, but I see nothing to indicate that this is glass. It could easily be real inclusions in polished quartz.

3rd Mar 2016 21:58 UTCOwen Melfyn Lewis

Vernon,

Help an old man over a stile here and indicate where you see a bubble in the pic? I can't see one.

However bad the seller's English may be, they seem to know to the difference in meaning between 'grass green' and 'green grass' ;-)

3rd Mar 2016 23:12 UTCGary Weinstein

All,

Over the years I have dealt in many gemstones from Brazil which look similar to that. They are most likely Actinolite crystals in Quartz though green tourmaline is also found. The "bubbles" he thought he saw are probably where the crystals break the surface and the edges of the softer material chip away.

Gary

3rd Mar 2016 23:33 UTCVernon

I may be wrong, but those look like bubbles to me. The point is green included quarts is rare and wouldn't be sold so cheap. Many of the people buying from them have no clue and leave good reviews, but you will see most have negative reviews from experienced buyers. They talk about receiving glass instead of quarts and glass for other items such as Ruby, Sapphire, Emerald, etc. Google search fake stones, gems, items, fossils, etc from China. You will see there is a huge influx of fake items coming out of China through Ebay and it is only getting worse.

3rd Mar 2016 23:56 UTCReiner Mielke Expert

They look like internal fractures to me not bubbles.

4th Mar 2016 00:22 UTCOwen Melfyn Lewis

Thanks for that, Vernon. Nicely marked. Bubbles are spherical or close to that . What you have marked (left) is no bubble and marked right looks discoidal to me and not spherical. Yes, indeed bubbles are common in glass and are also can be found in some synthetic crystals (sorts 'em out from from the mined kind).

To illustrate the point, here's a cobalt glass oval cut imitating a sapphire. The lighting is darkfield and the bubbles stand out like headlamps on a dark night as an immediate give-away of the fake (mainly top-right with a stand-alone beauty near the centre of the table. There are other more subtle signs too:

Turning back to your specimen. I can't hand on heart, say what it is from the pic and would want it on my bench before committing - but I don't think its glass. Quartz, possibly polished, and with epidote inclusions?

Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2024, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 25, 2024 13:24:31

Go to top of page