what exactly does that mean???

http://www.collectorsguide.com/fa/fa098.shtml

thanks for that...however i'm still a little confused. it seems that something called "chalk turquoise" could be stabilized, treated, or reconstituted...so if it says chalk turquoise, how do i know what i'm getting??? [?] what is considered "ok" to use in jewelry...i'm thinking stabilized or treated? is there a preference? obviously, the natural stuff is out of most people's price range. [:p]

Generally, chalk turquoise will be the lowest grade that you can find. Because most of it is too soft to use for jewelry, they grind it down into a 'chalk.' Then it is mixed with some sort of resin and compressed into a hard form (then made into beads etc.). So, in a sense it is stabilized (the resin makes it stronger and harder), it is treated (compacted and sometimes dyed), and it is also reconstituted (ground up and reformed).

Most turquoise is treated in some way. Much of the turquoise sold on sites like mine, R&T, Artbeads etc. is all stabilized. This simply means that a resin is added to the stone to harden and fill in cracks. Some of this turquoise is also dyed to achieve more blue/green colors.

You should be able to find more on turquoise grades by googling, or from Rings & Things gemstone index.

QUOTE: Originally posted by PotomacBeadCo Most turquoise is treated in some way. Much of the turquoise sold on sites like mine, R&T, Artbeads etc. is all stabilized. This simply means that a resin is added to the stone to harden and fill in cracks. Some of this turquoise is also dyed to achieve more blue/green colors. You should be able to find more on turquoise grades by googling, or from Rings & Things gemstone index.

Native Americans have always stabilized turquoise, but most often they dipped it in hot boar fat to do so. They did not dye their turquoise. I sell turquoise in my store and except for two strands that were incredibly beautiful and are clearly labeled as such, none is dyed. If it is dyed, vendors must tell you that, as it is no longer natural. Do not assume that all turquoise is dyed or that it's not. Ask your vendor to find out. But most important, buy from a reputable vendor. For example, those who will sell yellow turquoise (a contradiction in terms) are not honest about their product, as there is no such thing. I would suggest research the background of the stone, get familiar with a few concepts and when you plan on buying from a vendor at a show or a store, ask them these questions and listen to their reply. This will help you to know who to buy and not to buy from

Good luck,

Batel

QUOTE: For example, those who will sell yellow turquoise (a contradiction in terms) are not honest about their product, as there is no such thing. I would suggest research the background of the stone, get familiar with a few concepts and when you plan on buying from a vendor at a show or a store, ask them these questions and listen to their reply. This will help you to know who to buy and not to buy from

---
http://www.rings-things.com/gemstone/t.htm
Yellow Turquoise, Soft
From China's Hubei province, this soft stone is a natural turquoise but is usually dyed to achieve its deep yellow hue. We also believe it is wax-treated to harden the surface, or possibly stabilized with a resin.
----

We also had ours sent away and tested by a gemologist to confirm.

I have to disagree.

There really is chalk turquoise. Chalk turquoise is, as Nathan says, softer, lower grade turquoise that must be stabilized before using in jewelry. Stabilizing with resin both hardens the stone and darkens the color (just as getting a sponge wet darkens the color of the sponge.)

However, most of the stuff that is advertised as "chalk turquoise" is not turquoise at all. "Chalk turquoise" has become another misleading marketing term for simulated turquoise. Real chalk turquoise is sold as enhanced turquoise or stabilized turquoise.

The material sold as "Chalk turquoise" is mostly dyed magnesite. Magnesite is Magnesium Carbonate, MgCO3, a mineral that is not related to turquoise in any way. Turquoise is a hydrated phosphate of copper, aluminum and often iron. Turquoise is a variable mineral with a variety of chemical formulae representing it. One is Cu(Al,Fe3+)6[(OH)4(PO4)2 + 4H2O (sorry this forum does not do equations well) Turquoise is a copper mineral. ALL forms of turquoise contain copper. Magnesite contains NO copper.

Recently cutters have found a way to do a very nice surface crazing on magnesite. The fine lines are dyed brown or black to look like fine spiderweb lines in turquoise matrix. I've seen this crazed magnesite sold in natural white, dyed blue to look like turquoise and dyed pink to look like, I guess, "pink turquoise" or maybe coral.

Let me answer ~SunFire~'s original question

QUOTE: Chalk Turquoise what exactly does that mean???

When most vendors label a stone as "Chalk turquoise" they mean that it's a dyed simulation of turquoise.

I think using "Chalk turquoise" this way is very misleading. It's not even very descriptive. I think dealers use the name "Chalk turquoise" when they don't want to admit that it is not a real turquoise. For many years dealers sold stones cut from blocks of dye and plastic as "recon turquoise" or "reconstituted turquoise" that contained no "powdered" or crushed turquoise. "Chalk turquoise" is a new euphemistic name for a new and even better turquoise simulation.

For more on this, please see
http://www.beadandbutton.com/bnb/community/forum/topic.asp?TOPIC_ID=41094
http://en.wikipedia.org/wiki/Turquoise
http://www.rings-things.com/gemstone/index.html
http://www.luckygemstones.com/turq_informed_buyer.htm has some inaccuracies but admits that "Chalk turquoise" is not real turquoise. It DOES have pictures.

I have a collection of magnesite in white nodules, natural white, crazed and dyed versions. I need to photograph these and post them here and on my gem index pages.

Oops, our gem index is always out of date. It's a work in progress,,,,

There are 2 kinds of stone called "yellow turquoise." One is a relatively hard serpentine. Our gem index correctly says: Yellow Turquoise, Hard (aka Flower Jasper, Flower Turquoise, Chinese Howlite)
The harder version of the two stones known as "yellow turquoise," this stone is more likely a jasper or serpentine. We don't think this stone is dyed or enhanced. It is yellow with brown, green and red, much more varied than the dyed Hubei product (below). The black matrix in yellow turquoise is often attracted by a magnet and is probably hematite.

For the soft dyed product it says (as Nathan quotes) Yellow Turquoise, Soft
From China's Hubei province, this soft stone is a natural turquoise but is usually dyed to achieve its deep yellow hue. We also believe it is wax-treated to harden the surface, or possibly stabilized with a resin.

That's what we were told by our Hubei supplier but I now think it is wrong. As Batel says, there is no such thing as a yellow turquoise - it's another misleading descriptive name common in our industry. I'll have to do some more research on the soft version from Hubei and see if it is a magnesite, calcite or maybe a limestone that is dyed yellow.

Yes I'd be interested in finding out. We talked to a gemologist who did a test on ours, saying it DID have copper and that it did fit in the Turquoise family. But I'd like to know for sure!

I wonder what tests they used?
Perhaps the blue color comes from a copper based dye?
FMG had some tested , also, and said theirs was turquoise.

I think the only labs I'd be really confident in are ones like at the Univ of NM where they work with a lot of turquoise. GIA is really good for high end gemstones but the results I got from them for the serpentine called "yellow turquoise" and other inexpensive stones were of limited value. (I'll have to dig out their wording.) I'll also have to call Eddie Thomason at Thomason Stone Supply. At Tucson he had a display of his real stabilized turquoise and some very good looking dyed magnesite that had been lab identified as magnesite.
(www.thomasonstonesupply.com in Albuquerque is yet another reliable dealer in real turquoise.)

No I am talking about yellow turquoise... that is what they had tested. Unfortunately, I don't know the methods and was not there and I still have a lot to learn.

Everyone has a lot to learn. That's one of the wonders of this bead business, there are always new thing to learn.

As with many other stones, there is nothing wrong calling them by their real name. There is nothing wrong with the name magnesite, as it is a beautiful stone in itself. Similarly, why call something serpentine jade or new jade when serpentine in itself is beautiful too, fruit “quartz” for glass. I could probably go on with many examples, but no need. My opinion is that the naming thing is all about trying to get more money for something by associating the stone with more a valuable one.

Batel

In some cases I agree with you, Batel, that "the naming thing is all about trying to get more money for something by associating the stone with more a valuable one." Calling Magnesite "Chalk turquoise" is surely a good example of that.

In other cases we have descriptive names translated from Chinese into English. I think I've quoted the sign that a beadcollector.net member wrote down at the Beijing Gemological Museum: << 'Jade' in China describes all polycrystalline and cryptocrystalline mineral aggregates and a few non-crystalline materials that are suitable for carving and making into jewellery. The caracteristics are beauty, colour, moderate hardness, tough and fine texture, and as well as nephrite and jadeite includes opal, serpentine, quartz, turquoise, lapis lazuli, malachite, dushun yu, marble, natural glass, rhodocrosite, solalite, and rhodonite.>>

Obviously, we in the west consider only nephrite and jadeite to be "real jade."

Jasper names are another example of names that really have little absolute meaning. All the Oregon and Idaho picture jaspers that have very specific names are only named that because some rock hound called them that based on where s/he found them. Biggs Junction, Ohwee, Wild Horse, Bruneau, Windy Ridge are well known examples. Maybe we should just call them all picture jasper?

IMHO, Descriptive names are OK when they are not used to defraud or mislead the buyer.

Hey, old hippies, this has been a GREAT discussion. The info you and others are providing is hard-won and so helpful! Thanks you all of you for being so generous with your info.