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Listening Test Type B Jade Bangle

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Hi Arthur,

I am confused with the information in the internet on distinguishing an A grade jade bangle from a B grade one.

I hope that with your extensive experience, you could clarify my doubts.

1) I read that jade bangles with ‘flowering’ patterns ie, where the individual stone crystals are visible in some places, are definitely unbleached. Is it true?

2) For the sound test, is the ‘thud’ of a non-A-grade bangle to be taken literally? I have struck a grade B (or maybe it’s C) bangle and it produced a hollow echoing sound, like ‘clangggggg’, but not a ‘thud’.

As for my other bangles, one gave an unmistakable A grade sound (so I sort of compared it with the rest), some gave a high pitched sound without much resonance, some gave medium-pitched echoing sounds. But no thuds.

What do these mean or rule out? Are they conclusive? Thanks for reading and your kind attention.

Winnie


Hello Winnie

The ‘flowering’ patterns in a jade piece are the color of the very minute individual monoclinic crystals within a jade that is ‘locked’ in together as a massive habit.  They cannot be bleached away.  So whenever you see some flowering pattern it does not mean that the jade has not been bleached.

When a jade is bleached it will only remove some of the minute black spots or specks on the jade piece.  It may be hard to really determine whether a jade has been bleached by just eye-balling it with a loupe.

You must remember that ‘hearing’ the sound emit from a jade bangle when hit is only a ‘quick and dirty’ test.  This is especially useful when you are buying from jade dealers in a market place where you cannot run any gemological test.  It is by no means conclusive.

I have ‘listened’ to perhaps thousands of jade bangles throughout my years in the jade business.  I have ‘listened’ to sound as emitted from other types of bangles as well, examples are nephrite jade, lapis lazuli, agate, calcite and other minerals.  This is to enable me to distinguish other sound from other minerals and also to ingrain into my psychic so that when I hear the reverberating sound from other types of minerals I will be able to distinguish that there are not of jadeite jade material.

The jadeite jade picture above was a Type B Jade.  A few years back I bought 3 pieces of them at USD3,000 a piece from a known Burmese trader whom I have many years of dealing.  The reverberating sound is almost that of a Type A Jadeite Jade.  I was wrong and they turned up to be Type B Jadeite Jade when I ran an FTIR test on them.  Had I being right, then I could make a tidy sum from these 3 icy jade bangles.

So I blew 9 grand dollars.

When you use the ‘listening’ test, you must be aware that each jade bangle is unique and you have to use some judgment on your own.

I list some of the factors that you have to take into consideration:

1) The sound that emits from a Type A jade is a kind of reverberating resonance and not only a high pitch sound.  This means that when you hit a jade bangle the sound should be ‘clear’, ‘sharp’ and resonates within the jade bangle.  The longer the reverberating resonance the better the chance that the jade piece is Type A.  If it is high pitch and does not resonate then chances are it is a Type B jade.

2) The pitch and resonances as emitted depend on the cut, thickness and the ‘size’ of the jade bangle.

  • A jade bangle with a round inner diameter will resonate better than a flat inner diameter bangle
  • A thicker bangle will resonate better than a thin diameter bangle
  • A bigger bangle will resonate better than a smaller bangle.

3) The more translucent the bangle the better will be the reverberating resonance.  Hence, if you have a semi-transparent (note this term, as in icy jade) jadeite jade bangle, the resonance will be excellent.

4) You may have to test the sound by hitting it on all the 4 ‘corners’ of a bangle. Say, you start with a point on the bangle at 12 o’clock.  Then you must also test the sound emitted at 6 o’clock, 3 and 9 o’clock.  The main reason for this is that not all surface of the jade bangle may be impregnated with polymer.  There may be certain areas that a ‘manufacturer’ may pad it with heavy cotton wool so that polymers cannot penetrate.

5) You should not test a bangle with another bangle.  If one is the Type A Jadeite Jade and one is Type B, then you are only hearing the resonance from the Type A jade, while the ‘thud’ sound from the Type B is masked.  The best is to use an agate piece. (read here)

In order to acquire expertise in the listening test, you must test hundreds of samples and let the ‘tinging’ sound be impinged onto your psychic.  You may also have to test with known samples, that is, the jade piece must first of all be determined.

Best of wishes to all readers who may find the above post informative.  Do drop a comment if you have additional facts to add.

A Arthur

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I am a Graduate Gemologist trained at the Gemological Institute of America (GIA) in New York City, USA. I hold an MBA degree from Cranfield University, United Kingdom, and a Bachelor degree in Mathematics. My earlier profession was a banker until I found jade in Myanmar (Burma) in the early 90s. I have traveled to the fabled Hpakan Jade mines, and Mogok, the world’s famous rubies and sapphires mines in upper Burma, with my second son. Three of my children are also Graduate Gemologist, GIA, NYC and they deal in diamonds, gemstones and jade. 我是在美国纽约市的美国宝石学院(GIA)接受过培训的宝石研究学家。 我拥有英国克兰菲尔德大学的工商管理硕士学位和数学学士学位。我以前的职业是银行家,直到90年代初我在缅甸接触到玉石。我曾经和我的次子一起去过缅甸上流传说中的哈帕翡翠矿山和莫谷矿山, 莫谷矿山是世界上著名的红宝石和蓝宝石矿山。我的三个孩子都是纽约市GIA毕业的宝石研究学家, 他们专门处理钻石,宝石和玉石.

8 COMMENTS

  1. Hello Ivan

    Thank you for your comments again.

    Recording the sound given out by a jade piece when hit may be a bit difficult for me. I think sophisticated sound recording devices must be used. If I use a normal digital camera the essence of the sound may not be able to be captured so clearly. Moreover, it can be misleading.

    Jadeite Jade spectrum has 3 lines in 437.5nm and a doublet at 650. A broad band indicates that the jade has been dyed.

    Thank you again Ivan
    arthur

  2. Hi there, thank you very much for taking your time to post a comment which is very informative.

    I will write up about FTIR later.

    Yes, the polymer may fade with time. I will do a post on this as this is a very interesting question.

    We are always on the lookout for new imitation or polymer impregnated jade on the market. As you have mentioned that with new technology the impregnated substance may not fade so easily. The current polymer used by Type B jade manufacturers has an RI almost equalled to the RI of Jadeite Jade. This is to enable the jade to pass through the first test of jadeite jade using RI.

    Mutton fat jade is normally Nephrite. So far I have not come across polymer impregnated Nephrite Jade as there are ample supplies in the world.

    Thank you Desiree

    arthur

  3. Absolutely useful post! Thank you for the post!

    Can you record the sound of the type A and B and upload it here as well. It could be really excellent example for us as well.

    “The best is to use an agate piece. (read here)”<—- I think you should fix the link here.

    @About FTIR test,

    I remember that when you receive the result, there will be a rainbow color bar on the paper (I think its jade spectrum). The Type B will have one black line in the middle (easily to be seen) and the type C have two black lines. Of course, type A nothing is there in the rainbow bar. (I'm not really sure about this because I read this in some other source about Jade, so the info may be not correct.)

  4. Arthur,
    This listening test is useful, as you mentioned the it’s a quick dirty test & it requires also your experiences in listening different type of mineral, gemstones, your quick analysis on the object to make judgment. In term of proper test, we still need to conduct FTIR to check if the jadeite object has been enhanced or not. Can you please explain more about the FTIR test? 
    In term of the technique “impregnated with polymer” into jadeite, the impacted object will be faded in future. However, with new technology nowadays science can improve the polymer such that it has the same refractive index to jadeite & also its colour can stay permanently, do you think so? Have you seen any sample yet?
    With Mutton fat jade, do they also use those techniques to enhance?

    Thanks
    Rgds
    Desiree

  5. This is a very good post with a lot of information on the back to basis learning.

    thanks arthur
    stephen

  6. Thanks, Arthur, for the extremely detailed and useful reply, especially points 1 and 4. I think nowhere else in the internet will one be able to find this depth of info on this subject.

    Best regards,
    Winnie

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