Author Topic: internal cracks in paperweight  (Read 378 times)

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Offline AnnieQuilts

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internal cracks in paperweight
« on: January 19, 2014, 02:30:04 PM »
I recently bought a paperweight.  It looked like someone had dropped it because the inside had all these what looked like crack lines.  The main design was rows of tiny bubbles.  The seller said, that it had not been dropped but made that way intentionally by putting the paperweight in cold water while still hot after blowing to form these internal planes that look like crack lines to me.  You cannot feel any cracks extending to the surface at all.  I bought it because the lines/planes inside were actually quite pretty the way they caught the light. My question is - do they actually make paperweights with what look like crack lines inside?  I have not been able to find anything like this on the internet yet.


Offline glassobsessed

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Re: internal cracks in paperweight
« Reply #1 on: January 19, 2014, 02:57:37 PM »
Welcome to the board.

A photo of your weight would help a lot. It might have been made that way or the cracks could be as a result of stresses within the crystalline structure of the glass itself.

John



Offline mildawg

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Re: internal cracks in paperweight
« Reply #2 on: January 19, 2014, 05:31:43 PM »
Sounds like annealing cracks, where the glass is essentially cooled to quick causing it to crack.  I suppose it could be intentional for some but is typically not intentional.  Pics would help.


Offline KevinH

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Re: internal cracks in paperweight
« Reply #3 on: January 19, 2014, 11:33:39 PM »
With cracks inside the weight but not on the surface, then ...

1. It is unlikely to have been blown as that would imply a thin hollow ball.
(But many people use the term "blown" erroneously to mean "hand made". The term is also known on import labels for mass produced items out of China).

2. It would be a very skilled process indeed to drop a hot solid ball of glass into cold water and only fracture the inside!!!
KevinH


Offline Sach

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Re: internal cracks in paperweight
« Reply #4 on: January 21, 2014, 03:24:07 PM »
"Crackle" glass is made by briefly dipping hot glass into water.  This results in surface fractures that are easily detectible by touch, even if the glass is "healed" by reheating in the glory hole.  Internal fractures are the result the item being placed in the annealer too cold, an inadequate annealing cycle, or incompatibilities in the glasses used within the piece.  If the fractures seem to run along side a bit of color then incompatibility is the most likely answer.  If the fractures are essentially flat planes within the center of the weight, then it is most likely the piece was put away too cold and the annealing process was unsuccessful for that reason.

I too have been told by the seller that internal cracks are a design feature intended by the maker of the weight.  That story is pure BS.

It would be possible to crackle a small gather then encase that in additional glass.  This would result in a weight where small cracks would be visible running in a thin layer around the interior of the weight.  It would not result in flat planes radiating from the center of the weight.



Offline glassobsessed

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Re: internal cracks in paperweight
« Reply #5 on: January 21, 2014, 04:49:01 PM »
That story is pure BS.

Usually but not always.

Many paperweights where made at Mdina that were crackled, silver chloride was allowed to flood the cracks before further casing to give the yellow crackle that can be seen in the following two weights (currently on ebay):

http://www.ebay.co.uk/itm/Mdina-Paperweight-/131096913007?pt=UK_Art_Glass&hash=item1e85fc246f

http://www.ebay.co.uk/itm/Mdina-Glass-Paperweight-Signed-/261378410185?pt=UK_Art_Glass&hash=item3cdb5e06c9

John


Offline flying free

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Re: internal cracks in paperweight
« Reply #6 on: January 21, 2014, 05:21:15 PM »
I think Sach is referring to the particular weight the op is talking about John.
It sounds like we've not seen it but Sach has and knows what the cracks look like and therefore whether they were intentional or not :)
m


Offline Sach

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Re: internal cracks in paperweight
« Reply #7 on: January 22, 2014, 03:47:43 AM »
I think Sach is referring to the particular weight the op is talking about John.
It sounds like we've not seen it but Sach has and knows what the cracks look like and therefore whether they were intentional or not :)
m

I've not seen this particular weight but I've made all the mistakes I described.

I


Offline glassobsessed

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Re: internal cracks in paperweight
« Reply #8 on: January 22, 2014, 09:14:38 AM »
I have not heard that particular line from a seller yet but paperweights are fairly new for me. On the other hand, I must have made nearly every other mistake possible buying glass over the years. All that experience, good and bad does help to inform though.

This was probably my biggest howler: http://www.glassmessages.com/index.php/topic,50802.msg287670.html#msg287670


 

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