I have had good success doing in situ polishing on some artifacts for
microscopy using a small dowel with polishing clothes attached to the
end and run on a drill press. The spot is relatively small and good
enough for a high quality microscopic examination... something to
think about in any case.
Aaron
On Fri, Oct 19, 2012 at 7:56 PM, David Scott <[log in to unmask]> wrote:
> 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.
>>>>>
>>>>>
>>>>
>>>> =
>>>
>>>
>>
>
--
Aaron Shugar
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