[Jewelry making - Article 00543] - [Orchid] Sun spangled inclusions in natural amber

[jake]

========[ Invite a Friend - http://www.ganoksin.com/invite.htm  ]========

    This is from the GIA, I will post the entire letter at the end of
    this. "Your observations concerning so-called nasturtium leaves or
    sun spangles are for all practical gemological purposes completely
    correct." 

    Do not take any of this personal, as it is not intended as such.
    That you read something different is not surprising, however some of
    what you read is hardly accurate. Never just assume anything posted
    on the Internet is true, it may or may not be, not everything in
    print is true, also. I did not take offence with the tone of your
    post. I was put off a bit by the effort, time, and a reply takes. Not
    believing me is one thing, arguing that a recognized authority(s) do
    not know what they are talking about because someone said different
    is another. If you can keep an open mind perhaps you will learn
    something. 

    I will start with this first, you wrote "Heating it in oil. will
    clarify it, but those round fractures (more commonly called "sun
    spangles") are a tell-tale sign that this has been done." 

    I had thought that using the IGS (International Gem Society) as my
    reference would be enough. This is the exact quote, "Another popular
    type of inclusion are "star spangles." These internal fractures
    radiate from a central point. While quite attractive, most are human
    induced." (Meaning, not all are human induced.) 

    Some amber contains inclusions known as sun spangles, with the
    appearance of nasturtium leaves, although most of this is seen in
    treated amber." (Again, note; not all with this is treated.)

    http://therossjewelrycompany.com/gemstone.cutter.atlanta.amber.html 

    One should pay particular attention to what is on the bottom of that
    page, the above, "We are proud members of the following jewelry
    industry organizations." the reason is this, always take the word of
    a recognized authority. That the statement that this inclusion is
    always proof of treatment is in circulation is unfortunate, it is not
    true. At the same time seeing this, one, unless otherwise known,
    should assume it has in fact been treated, this would be correct most
    always, as said. 

    You wrote, "Again in regards to blitsen, or sun spangled, "They
    don't really count as an "inclusion." At the same time only one of
    your reference links you used to say this disproved everything I
    said, had any mention to this subject at all, they in fact called it
    an inclusion. (There has been email between us, Dear Jake, Thank you
    for sharing your knowledge about sun spangles in amber.) 

>     While clear Baltic amber (even with "spangles") is preferred by
>     some to amber in its natural state (which is why the heating
>     process is done), I doubt that naturally clear amber would ever be
>     treated to produce the fractures - it would be vandalism, like
>     intentionally cracking a flawless gem.

    If you had ever ordered amber (pre-cut) from a cutting house you
    would never had made this statement, it is in fact commonly done, as
    it is popular. On Baltic amber they will ask you what color (shade)
    then if you want high or low dome on the cabochon, they next ask if
    you want it blitzed. 

    You wrote, "I don't believe that heat and pressure have much to do
    with the formation of amber from tree resin." This is the answer: 

    "The complete transition from resin to amber has to have two
    additional factors present: heat and pressure. Heat and pressure may
    support the process of polymerisation and turpene evaporation but
    their full effect upon the formation of amber is not fully
    understood." http://www.gplatt.demon.co.uk/typesof.htm 

    Here is the result of the lack of the above. "Borneo amber is of
    Middle Miocene age. Specimens that come from sandstone beds are dark
    and undoubtedly true amber (no reaction with alcohol), however
    specimens that come from clay beds of the same age are yellow and are
    copal (react with alcohol). Clearly the kind of sediment is very
    important in this process."
    http://www.gplatt.demon.co.uk/transfor.htm 

    You wrote, "Quenching has no part in the process, " no again. I
    wrote that I amused that quenching (in water) did this. As this was
    unimportant to me I did not investigate, at the same time I would
    have been willing to place a small wager that this was the case, then
    again for all I knew for a certainly was some other liquid may have
    been used. Therefore I did not state it as fact. Here is the answer. 

    "Blitzer: is the German name of artificially reflecting fissures,
    which develop after 'cooking clear' the amber in oil, followed by
    cooling in water." The Amber Dictionary-
    http://www.museum-albersdorf.de/BERNSTEN/LEXICON.HTM 

    This I do take offence at, as it was basically how your letter
    started. "Unfortunately, most of what is written on amber comes from
    old references; accurate when written as far as was known, few
    consult later archeology findings." this was taken out of context,
    that is not honest. Most on the history of amber will state the
    oldest found is in France, dating from the Neolithic, one written
    later mentioned that in Cheddar England beads dating to 8,000 BC have
    been found. However, read this. "Worked amber dating back to 11,000
    BC has been found at archeological sites in England." Again, "The
    earliest evidence that amber was known about, mined, and worked with
    in the Baltic Sea/Gdansk area dates from between 8000. (BC)" I have
    an archeological report, separate from this, referring to "workshops"
    dating from this period. 

    Below, is what I wrote to the GIA (edited) and the response. 

        First I do not know if this, your office, is the right place to
        ask, I apologize now if this question should have been directed
        elsewhere (to a different department). 

        Perhaps you could help clarify something. I wrote (to a list)
        that, quoting Don Clark, president of the IGS (International Gem
        Society), Another popular type of inclusion are "star spangles."
        These internal fractures radiate from a central point. While
        quite attractive, most are human induced." (Meaning, not all are
        human induced.).... 

        I feel this is of some importance as there is so much mis and
        dis-information circulating on the Internet as truth regarding
        gems in general, all of which is often repeated 

    Response: 

        Thank you for your e-mail to our President, Donna Baker, which
        has been turned over to me for a response. 

        Amber and related younger fossil resins are one of my favorite
        gem materials from a micro standpoint since they give us a unique
        window on ecosystems from the ancient world and their fluid and
        gaseous inclusions also allow us to examine aspects of climate
        change when compared to air and atmospheric water samples
        collected today. 

        Your observations concerning so-called nasturtium leaves or sun
        spangles are for all practical gemological purposes completely
        correct. As you probably know these inclusions develop in cloudy
        amber during the heating stage of the clarification process where
        countless minute bubbles migrate to the surface and escape their
        host when the host is sufficiently softened. A slight vacuum can
        help in this process if essentially clear treated amber is the
        goal. In many cases however, totally clarified amber is not the
        goal, since some feel that so-called nasturtium leaves or sun
        spangles look natural, and add a natural aspect to the treated
        material. 

        These treatment-induced features are nothing more than discoid
        decrepitation halos, really no different in many respects from
        that those that occasionally occur in peridot and feldspars, and
        also in many heat-treated corundums. 

        During the clarification process many bubbles can coalesce into
        one and then expand rapidly as pressure builds causing a rupture
        in the form of a disk. As cooling takes place the disk shrinks
        and wrinkles in a uniform manner producing the texture on the
        inner walls that, to some observers, make it look like a natural
        inclusion of organic origin. 

        A great deal of fraud has resulted, either because of complete
        dishonesty, or through ignorance. Please note however that not
        all discoid inclusions in amber are the result of treatment
        (although, certainly the vast majority are). Most are obvious
        indicators of treatment, but when only one or two discoid
        features are present as inclusions a close microscopic
        inspection of the host material is required. 

        Fluid inclusions (droplets of rain or dew) and complete
        arthropods or insects or insect parts, as well as any botanical
        inclusions do not survive the clarification process in any
        recognizable form. If an amber specimen that contains a discoid
        feature also contains any of these recognizable inclusions you
        can be sure it has not been treated through a clarification
        process. Note also that "nasturtium leaves or sun spangles" can
        also be induced in plastic through a similar processing (see
        Photoatlas of inclusions in Gemstones Volume 2 page 303), so the
        presence of such inclusions does not even guarantee that the host
        is amber. 

        I hope this has been of some help. If you have any additional
        questions you can contact me through my e-mail address or by
        phone at xxxxxxxxxxx. 


 
____________________________________________________________________
T h e   O r c h i d   L i s t
Open Electronic Forum for Jewelry Manufacturing Methods and Procedures
____________________________________________________________________
Orchid FAQ:
~ http://www.ganoksin.com/orchid/faq.htm
Orchid Archives:
~ http://www.ganoksin.com/orchid/archive
Orchid Galleries:
~ http://www.ganoksin.com/orchid/gallery.htm
Invite a Friend:
~ http://www.ganoksin.com/invite.htm
____________________________________________________________________
Tips From The Jeweler's Bench - Article Archive
~ http://www.ganoksin.com/borisat/tip_sear.htm
The Jeweler's Selected Bibliography List
~ http://www.ganoksin.com/jewelry-books
Buy Orchid Jewelry:
~ http://www.ganoksin.com/shop
____________________________________________________________________
-Unsubscribe:
-Email: orchid-request AT ganoksin.com Body=unsubscribe subject=blank
____________________________________________________________________