Lapidaryforum.net

Please login or register.

Login with username, password and session length
Advanced search  

News:

Welcome new members & old from the Lapidary/Gemstone Community Forum. Please join up. You will be approved after spam check & you must manually activate your acct with the link in your email

Congratulations to Stonemon and his Blue Biggs Jasper Cab!

 www.lapidaryforum.net

Another cabochon contest coming soon!

Pages: [1]   Go Down

Author Topic: Question About Odd Turquoise Conglomerate?  (Read 655 times)

0 Members and 1 Guest are viewing this topic.

ileney

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 353
Question About Odd Turquoise Conglomerate?
« on: May 11, 2018, 01:39:29 PM »

I have some very nice untreated Kingman turquoise that was my dad's that I had previously asked and received information about here. I noticed on ebay that a number of sellers (but it may all be the same seller operating under different names) have posted what they claim is natural, untreated turquoise, but it looks nothing like mine. Sometimes they identify the name of the mine, sometimes they indicate it is "hubei" (presumably meaning from China), and sometimes they don't say anything about the source. It generally sells fairly cheap and many of the pieces are very large. Out of curiosity, I bought a few pieces but am stumped. Is this what lower grade turquoise looks like, is this a fake, is it a conglomerate of some kind, or what? Posted below are a few pictures of some pieces for your thoughts. The first three are small stones. The last two pictures are of the same very large 1200 ct. stone. The small stones have no smell and the black one is very light weight whereas the larger brown one is relatively heavy. The larger stone definitely has an acrid, possibly paint-like smell to it and is heavy. Supposedly, it is all untreated, but I sincerely doubt that.
Logged


Orrum

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 739
Re: Question About Odd Turquoise Conglomerate?
« Reply #1 on: May 11, 2018, 04:37:31 PM »

Turquoise is valued for its flaws. Pits, cracks, vugs etc. Also for its matrix of non turquoise rock. Pure blue turquoise like you see at bike rally etc is usually plastic or ground up chalk turquoise mixed in epoxy and pressed intimate forms. Your stuff looks very intetesting. 95 percent of all turquoise is stabilized. The other 5 percent is gem grade turquoise and we can't afford it and most folks won't ever even see it!
Logged

ileney

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 353
Re: Question About Odd Turquoise Conglomerate?
« Reply #2 on: May 11, 2018, 06:54:16 PM »

Huh. Well, my dad got his old turquoise 40+ years ago and it came direct from the mine and was not treated, but it also doesn't have very much by way of pits, vugs or even  all that much non-turquoise matrix, and I think it is gem grade, though none of the pieces are huge, hence my confusion. It looks and feels nothing like the new stuff. Like I say, the large piece of new stuff has a smell, so I assume that is something they used to stabilize it however much they claim it's natural. The other pieces might be natural ... or might use a process that doesn't leave a smell or anything. I have no idea what it will look like cabbed. Do people usually follow the contours or slab and cab this stuff the way they would non-turquoise material?
Logged

lithicbeads

  • Administrator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2425
Re: Question About Odd Turquoise Conglomerate?
« Reply #3 on: May 11, 2018, 07:29:10 PM »

 The rock in the third picture is exactly like what the Chinese used for hundreds of years to make focal beads prized in Tibet. Fakes are now commonly used to make this type of bead.
Logged

ileney

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 353
Re: Question About Odd Turquoise Conglomerate?
« Reply #4 on: May 11, 2018, 08:08:31 PM »

Great! Thank you for the information. Well, in that case maybe these were a good buy. I guess the best thing for me to do is to try to slice/cab  and/or carve them and see what happens. Oddly enough, I had drawn out a design for a pendant inspired by viewing ancient Chinese locks, so maybe I will slab and see if I can carve the design I have in mind in this material. I'll post the results at some point if I'm ableto do it.
Logged

rocks2dust

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 326
    • rocks2dust items on ebid.net
Re: Question About Odd Turquoise Conglomerate?
« Reply #5 on: May 12, 2018, 11:13:02 AM »

If you are very confident that it is untreated, save your cutting scraps. It may be worth spending the money to have it tested by someone who has access to XRD or similar equipment and is able to confirm no treatment (that will raise the price you can get, as Orrum said) and/or whether the pieces contain more turquoise or other, rarer minerals (like chalcosiderite and/or faustite). Having the test results would certainly support a higher price.

Turquoise has been resin-treated for the last 70 years or so - just about as soon as plastic resins came on the market, they began to be applied to turquoise. Even before that, for thousands of years, water glass, waxes, tinting and outright fakes were being produced, so age alone isn't a sure sign. The breakdown of resin treatment may be causing the odor you smell in that one piece.
Logged
r2d

surplus odds and ends that I have on ebid.net
· Xtra gemstones
· Xcess fossils, minerals and rough
· Everything else

Orrum

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 739
Re: Question About Odd Turquoise Conglomerate?
« Reply #6 on: May 12, 2018, 02:59:44 PM »

Horse urine to make it bluer, boiling in various animal fat to make it a little more stable and a lot shinier. Old indian pawn has a turquoise stained by human skin oils, gives a patina
 Don't remove or clean it or the silvet, copper etc because that will lower the value. Modern treatments of most gemstone cannot be determined by labs if the ultra modern methods are used.
Logged

palmwood13

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 74
Re: Question About Odd Turquoise Conglomerate?
« Reply #7 on: May 12, 2018, 06:47:15 PM »

Wow knowing what i have read here buying turquoise is very risky. Love the information we gain from this forum. Thank you. i bought several rings with turquoise in the early sixties from the Navaho jewelry makers. Don't know if it is real or not.
Logged

ileney

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 353
Re: Question About Odd Turquoise Conglomerate?
« Reply #8 on: May 15, 2018, 10:04:46 AM »

I feel certain most of the new stuff I bought is treated even though only the two larger rocks have any sign I can detect. I feel equally certain that the remainder of the pound my dad bought at cost from the son of a patient whoi owned a high-end jewelry store specializing in turquoise and native jewelry, and which had been obtained by him directly from the mine, was totally untreated. He also bought some untreated Kingman 40+ years ago at the big NYC gem and mineral show (high end show that I think was held either at Madison Square Garden or the Javitz Center), but though it was a high end show, you can never be sure it is what is stated. It does look smell and feel totally untreated though. Would it really be worth it to get it tested for such small amounts?
Logged
Pages: [1]   Go Up
 

Page created in 0.117 seconds with 41 queries.