large slag stringers may indeed show up on an x-radiograph but if not,
the blade obviously cannot be cut in any way to investigate as we
would normally do. As this technology is available in Egypt, although
it may not be sufficient to answer the question, it would be a
start.....all the best...David
Quoting Lee & Elizabeth Sauder <[log in to unmask]>:
> I'm sure this is a really stupid question, but maybe one of you
> would take the time to answer it.
>
> From the photos on the internet, it looks like the dagger is in
> fabulous condition, with uncorroded metal showing. Why can't you
> just look for slag stringers to tell you if it's smelted or meteoric?
>
> Lee
>
> -----Original Message----- From: David Scott
> Sent: Thursday, October 18, 2012 6:37 PM
> To: [log in to unmask]
> Subject: Re: King Tut's iron blade
>
> It is sometimes possible to see microstructural detail in an x-ray
> radiograph....especially if the artefact in question might have a
> slightly corroded Widmanstatten pattern if meteoric....different
> phases in the Fe-Ni series may show up in a blade in the same way as
> pattern welded sword blades have done in the past, with different iron
> and iron-carbon or iron-phosphorus regions, so this might be possible
> in Egypt if the conservators can get to work on it.....all the
> best...david
>
> ....Quoting Michael Notis <[log in to unmask]>:
>
>> Ok-I will chime in. There is a synchrotron in Jordan that Egypt has
>> a cooperative program with
>> (this is a broad international effort). The problem is that no
>> matter what photon energy source you use
>> the escape depth is still limited to the near surface layer so that
>> it holds little benefit over a handheld XRF.
>> XRD (which does produce thru-thickness diffraction patterns) will
>> give you information on the structure
>> of the crystalline phases but these must be present in significant quantity.
>>
>> I agree that LA-ICPMS seems to be the way to go.
>>
>> Mike Notis
>>
>>
>> On 10/18/12 1:56 PM, Ernst Pernicka wrote:
>>> Since you cannot bring a synchrotron to Egypt this would require temporary
>>> export. This is not possible, but if it were, LA-ICP-MS would still be the
>>> method of choice. It can be performed on large objects too.
>>>
>>> -----Ursprüngliche Nachricht-----
>>> Von: Arch-Metals Group [mailto:[log in to unmask]] Im Auftrag von
>>> Killick, David J - (killick)
>>> Gesendet: Donnerstag, 18. Oktober 2012 19:20
>>> An: [log in to unmask]
>>> Betreff: Re: King Tut's iron blade
>>>
>>> I agree with Ernst that LA-ICPMS would be ideal, but unfortunately there is
>>> no chance that anyone would be allowed to drill samples like the King Tut
>>> blade. Perhaps synchrotron radiation would be best, but I know little about
>>> it. I do know that it is non-destructive, can be done on whole artefacts,
>>> yields chemical composition for both major and trace elements (but to what
>>> detection limits??) and - most interestingly for meteoritic iron - can also
>>> provide metallographic parameters such as grain size, residual stress and
>>> spatial distribution of elements. If Brian Newberry or Leslie Frame are
>>> reading this, could they comment on the potential application of the
>>> synchrotron to this problem?
>>>
>>>
>>>
>>> ________________________________________
>>> From: [log in to unmask] [[log in to unmask]]
>>> Sent: Thursday, October 18, 2012 9:40 AM
>>> To: Arch-Metals Group; Killick, David J - (killick)
>>> Cc: [log in to unmask]
>>> Subject: Re: King Tut's iron blade
>>>
>>> From the site of Kerkenes Dag we have some iron we are looking at,
>>> from Anatolia but from the 7th century BC, a little later. Regarding
>>> the analytical determination of whether the iron is smelted
>>> iron-nickel alloy or meteoric, this could still be hard to do, for
>>> example the Mundrabilla fall in Western Australia has 7.7% nickel,59.5
>>> ppm gallium, 196 ppm germanium and only 0.87 ppm iridium, so on
>>> corroded archaeological artefacts determining here the amount of Ir at
>>> less than 1ppm would not be easy..certainly worth trying and a pity
>>> that the hand-held XRF instruments would not really be able to help
>>> here....all the best...david
>>>
>>> Quoting "Killick, David J - (killick)" <[log in to unmask]>:
>>>
>>>> Many thanks to Thilo for making this copy available. Unfortunately,
>>>> as Ernst points out, it does not solve the problem of whether this
>>>> is smelted or terrestrial iron. This question really needs to be
>>>> properly investigated. If I remember correctly, Michel Valloggia
>>>> discusses (in Mediterranean Archaeology 14, 2001) the slightly
>>>> earlier letter from Armana in which a Hittite ruler makes excuses to
>>>> his Egyptian counterpart for not sending the iron that the latter
>>>> had requested, and he (Valloggia) argues that the Tutankhamum
>>>> dagger is one such gift. Why is it necessary to know whether this
>>>> object is meteoritic or smelted iron? Because it is one of the
>>>> best-preserved iron objects from the period when iron was just
>>>> starting to become available to elites in Anatolia (during the New
>>>> Hittite period, 1400-1200 BCE). There are few contemporary iron
>>>> artefacts known from Anatolia itself - most of what we know about
>>>> Hittite iron is from contemporary documents.
>>>>
>>>> Non-destructive measurement of Ga, PGE and Co on the blade could be
>>>> done either by PIXE or by synchrotron radiation. Unfortunately, as
>>>> far as I have been able to determine by asking Egyptologists,
>>>> neither technique is available in Egypt, and Egyptian policy on
>>>> antiquities prohibits the temporary export of artefacts for
>>>> scientific analysis. This is why the study of archaeometallurgy in
>>>> Egypt lags so far behind that in the rest of Eurasia and Africa. As
>>>> Michel Wuttman wrote (also in Mediterranean Archaeology 14, 2001) we
>>>> know little more today about the development of metallurgy in Egypt
>>>> than we did in 1960.
>>>>
>>>>
>>>
>>> =
>>
>
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