We encounter it a lot. Common on civil war destruction sites. dave
On Thu, Nov 11, 2010 at 9:26 PM, Patrice L. Jeppson
<[log in to unmask]>wrote:
> I have seen ceramic fragments at the site of an early 19th C house fire
> that exhibited substantial spalling. The fragments looked pockmarked.
>
> On 11/11/2010 10:49 AM, Susan Walter wrote:
>
>> Not at all near salt water; inland a 2 hour drive from the ocean. And the
>> locus is on a low hillside with an intermittant stream a few hundreds of
>> feet away.
>>
>> One thing I did not mention was this particular site is supposed to have
>> existed less than 3 years, and was burned out. And there have been
>> wildfires through the area for hundreds of years, though it was spared that
>> during the last few years of our infernos.
>>
>> Has anyone seen this splitting/spalling effect as a result of fire?
>>
>> ----- Original Message ----- From: "Benjamin Carter" <
>> [log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Wednesday, November 10, 2010 4:29 PM
>> Subject: Re: split ceramics
>>
>>
>> Susan and other Histarchers,
>>>
>>> Could it be salt water getting into the sherd? When salt water dries,
>>> the formation of crystals can cause ceramics to spall/split.
>>>
>>> Nearly all of my white earthen ware ceramics from a coastal Maine site
>>> (c. 1800) were split. I think it was due to a combination of freeze/thaw
>>> cycles and salt water. At this point most are from relatively close to
>>> the surface.
>>>
>>> Ben Carter
>>>
>>> On 11/10/2010 6:18 PM, Susan Walter wrote:
>>>
>>>> Hmmm, the site is in San Diego County...
>>>>
>>>> ----- Original Message ----- From: "Mark Branstner"
>>>> <[log in to unmask]>
>>>> To: <[log in to unmask]>
>>>> Sent: Wednesday, November 10, 2010 11:40 AM
>>>> Subject: Re: split ceramics
>>>>
>>>>
>>>> Susan,
>>>>>
>>>>> I don't know what part of the country that you're working in, but
>>>>> "frost spalling" is a relatively common phenomenon ...
>>>>>
>>>>> Essentially, moisture gets into the porous fabric of the pottery and
>>>>> it splits the pottery when it freezes during the winter. It
>>>>> certainly does not happen all the time, but it does occur with some
>>>>> regularity. Sometimes just the glaze spalls off the fabric, but the
>>>>> fabric itself can split.
>>>>>
>>>>> Mark
>>>>>
>>>>>
>>>>> Nov. 10, 2010
>>>>>>
>>>>>> Hello all,
>>>>>>
>>>>>> I have a site with several sherds of transferware that are split so
>>>>>> that there is a transferware / glazed surface on one side and the
>>>>>> paste interior on the other side.
>>>>>>
>>>>>> This makes them about 1/8 inch thick. They tend to be about 1 inch
>>>>>> long, and about 3/4 inch wide.
>>>>>>
>>>>>> The edges are not shaped; in "plan" view the pieces are
>>>>>> miscellaneously trapezoidal.
>>>>>>
>>>>>> In appearance they somewhat remind me of porcelain pin
>>>>>> trays/childrens toy tea trays that are decorated and glazed on the
>>>>>> top and bisque on the bottom, except these transfer pieces are not
>>>>>> smoothly finished on the bottom ("bisque") like the porcelain items
>>>>>> are.
>>>>>>
>>>>>> I do not think these were made intentionally.
>>>>>>
>>>>>> I've not seen so many of these at one site before. Has anyone
>>>>>> knowledge of what did this?
>>>>>>
>>>>>> Thanks every one,
>>>>>>
>>>>>> S. Walter
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>>
>>>>> Mark C. Branstner, RPA
>>>>> Historic Archaeologist
>>>>>
>>>>> Illinois State Archaeological Survey
>>>>> Institute of Natural Resource Sustainability
>>>>> University of Illinois at Urbana-Champaign
>>>>> 209 Nuclear Physics Lab, MC-571
>>>>> 23 East Stadium Drive
>>>>> Champaign, IL 61820
>>>>>
>>>>> Phone: 217.244.0892
>>>>> Fax: 217.244.7458
>>>>> Cell: 517.927.4556
>>>>> [log in to unmask]
>>>>>
>>>>>
>>>>> When you think of that perfect retort five minutes after the
>>>>> conversation is over - that's when you're:
>>>>>
>>>>> "... bursting with the belated eloquence of the inarticulate ..."
>>>>>
>>>>> Edith Wharton in the "The Age of Innocence"
>>>>>
>>>>
>>>>
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