got a mystery here

[unclemac]

a friend of mine has been following this on a beach glass site she is a member of. the poster says it weighs 200 lbs. and they had to drag it up an (ocean) cliff with a winch. it is cylindrical, is is glass, not slag, has a dimple on the top and yes, that is an apple for comparison.

any ideas as to what this is?

 

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[smokeythecat]

A very cool thing. Was there a glass foundry nearby. Could be the end of a "melt" which was discarded.

 

[unclemac]

no foundry nearby, have no idea if it is a remnant.

 

[Tpmetal]

The accomplishment to anneal something that thick would be like over a month easy. Wtf is that?

 

[Tpmetal]

Any cracks running through it?

 

[digger460]

What is that

 

[unclemac]

Any cracks running through it?

no cracks...lots of aparent beach/sand abrasion...one fellow who looked at it discribed it as purpose made and high quality.

 

[Tpmetal]

Not being cracked I would say it was purposely made. A piece of glass that size would not survive being made without slowly cooling(annealing). So they wouldn't have gone through that trouble if it was cast off or end of a melt. The dimple is probably from when it was all hot during casting and as it shrank when it cools, it pulls that dimple into the forum. What it is for, I have no idea. As for all the wrinkled surface texture I'm not sure whats going on there, could be a few things. Could have been cast at a colder temp not quite smoothing the edges, could be texture from what ever mould was used, could be from shrinkage in the process.

 

[TommyB]

That may be cool to have all the edges polished out. Result may be a huge clear glass table or seat.
Cool find !!!

 

[sandchip]

Nautical lens or window that would be subject to high pressure? Very cool find, for sure.

 

[unclemac]

Nautical lens or window that would be subject to high pressure? Very cool find, for sure.

boy howdy...that would be some pretty fantastic high pressure....

 

[bloovey]

awesome find, very interesting, is it natural or man made?

 

[unclemac]

man made for sure

 

[Plumbata]

I agree with TPmetal, with the dimple/concavity and apparent cooling lines on the sides I doubt it was created for any other purpose but to be re-melted. My hunch is that it was a glass "ingot", probably a special blend of glass like a proprietary leaded crystal or other specialty glass that most manufacturers wouldn't have been able to make, cast into this crucible-friendly form and supplied to smaller-scale manufacturers of glassware or art glass. Being big and heavy and inconveniently sized for purposes aside from efficient shipping suggests it may be a European import.

 

[digger460]

That may be cool to have all the edges polished out. Result may be a huge clear glass table or seat.
Cool find !!!

Might want to re-enforce the floor tho That would be a nice table for sure!

 

[Tpmetal]

I agree with TPmetal, with the dimple/concavity and apparent cooling lines on the sides I doubt it was created for any other purpose but to be re-melted. My hunch is that it was a glass "ingot", probably a special blend of glass like a proprietary leaded crystal or other specialty glass that most manufacturers wouldn't have been able to make, cast into this crucible-friendly form and supplied to smaller-scale manufacturers of glassware or art glass. Being big and heavy and inconveniently sized for purposes aside from efficient shipping suggests it may be a European import.

There no point in making a glass ingot as it will crack and break with out annealing. Glass is shipped in cullet, basically smashed up glass chunks or small clipped pieces from a furnace. To cost to anneal each ingot that large would make it pointless to do. There seems no reason to make it that big in one piece unless it had a use.

 

[WaterScoop]

Possible lighthouse lens Check image below

 

[unclemac]

that idea was tossed around too....but such a lens doesn't need to be 200lbs or so thick.

 

[ltd063]

I would agree with your words. You definitely have a mystery on your hands. Let us know if you find out more information.

 

[Tpmetal]

that idea was tossed around too....but such a lens doesn't need to be 200lbs or so thick.

Unless from pre 1819? when the fresnel lens was implemented in light houses. Not sure what they looked like before the fresnel.