Topic: How was this made? Graal? Fused? I'm stumped.

[krsilber]

I've been out of town for a few days, and I'm just now getting back to this thread.

Thanks, Adam, for having a look at it, as I requested.  The graal idea was a shot in the dark, and quickly abandoned (Vic's jazzy work was mentioned in another thread recently; I didn't know he was a friend of yours).  I understand how the "donuts" could have been added to the piece, the thing I'm confused about it their decoration.  The brown is straightforward, it's the black that gets me:  the donuts are outlined in black, the black lines on them seem to penetrate the celadon more than the brown (as seen on the bottom), and the lines are quite thin and well-defined.  Just before leaving town I had a look in one of my books showing a couple somewhat similar pieces, and once I hit the road I started thinking about it...what if the black lines started as threads of glass (rather than powdered) that were marvered into the pre-formed donuts?  And the backs of the donuts maybe dipped in black powdered glass to create the outlines?  So the donuts would be more like marquetry than like trails.  Just an idea I had as I rolled through boring MN farmland.

The book I was looking at (Ricke's Glass Art, Reflections of the Centuries) shows a bowl/vase that reminded me of this, with the description, "Lampblown.  Assembled in montage technique.  The embedded band [which is sorta similar to the donuts] is striped with colored enamel canes."  Can montage be done on blown, cased glass?

[Ivo]

The Montage technique is a specific lampwork technique developed by Albin Schädel in Lauscha.

[Frank]

The discs are probably marvered on and distorted in the blowing.

[krsilber]

The discs are probably marvered on and distorted in the blowing.

This still doesn't tell me how the thin, sharp black lines and the black outline are achieved.  I understand how the piece could have been assembled, it's those details that have always been puzzling to me.  How do you get such a regular black outline, even on the bottom, in areas of the celadon where the surface has been ground away?  How is it that the thin black lines penetrate the celadon more than the brown?  How do they remain distinct from the surrounding brown areas, and retain their sharpness?  It is questions like these that made me at first wonder about graal, and whether they could have been scratched in and painted on (though, as I said, I've abandoned that idea).

[Cathy B]

The brown is straightforward, it's the black that gets me:  the donuts are outlined in black, the black lines on them seem to penetrate the celadon more than the brown (as seen on the bottom), and the lines are quite thin and well-defined.

A guess, for Adam  to confirm or deny: Rolled in brown first, maybe even reheated slightly, then coated in the black powder. If then applied as a trail, the disks will be quite thick, and the pattern occurs when the disks are flattened. The edges are compressed leaving more black and brown powder there, forming the outlines. The As the disks distort and stretch during the blowing process, the marbelling effect occurs. How does that sound?

[krsilber]

Great to see another guess!  Thanks for adding another hypothesis, Cathy.  I'd thought about the marbling effect being caused by stretching or marvering, too, like the effect you get in stretch glass.  I couldn't figure out how the brown alone would be stretched to reveal black but not the celadon underneath in the same manner, or why the black lines would go deeper. 

I've given this a lot of thought, but not having worked directly with hot glass it's hard to know all its behavior except by imaginary reconstruction of finished pieces.  Sometimes I make it more complicated than it actually is.

I just realized something - the middle of the bottom shows a patch where the brown covers the black; very little shows through.  I noticed this before, but now I wonder if its significance is that the piece wasn't marvered there much, and consequently the brown wasn't pounded past my imaginary network of thin pieces of black glass.  But I'm probably grasping at straws.   

Hee hee, from this and my skeleton mold thread and others, can you all tell I like to figure out precisely how this stuff was made?

[azelismia]

they look like crystals that have been grown out like on pottery with the crystalline glaze. I wonder if there is some way to glaze a glass piece and bake it for the required amount of time?

[aa]

A guess, for Adam  to confirm or deny: Rolled in brown first, maybe even reheated slightly, then coated in the black powder. If then applied as a trail, the disks will be quite thick, and the pattern occurs when the disks are flattened. The edges are compressed leaving more black and brown powder there, forming the outlines. The As the disks distort and stretch during the blowing process, the marbelling effect occurs. How does that sound?

A very fair hypothesis!

  Sometimes I make it more complicated than it actually is.

It would be impolite to disagree!

the middle of the bottom shows a patch where the brown covers the black; very little shows through.  I noticed this before, but now I wonder if its significance is that the piece wasn't marvered there much, and consequently the brown wasn't pounded past my imaginary network of thin pieces of black glass.

Incorrect. It was marvered just as much as the other trails, otherwise it would be raised from the surface of the vase.

But I'm probably grasping at straws.   

Correct!

Conclusion: I don't think anybody is going to be able to add much that will shed any more light on how this piece was made, unless someone is able to identify the maker and then we can ask them how they did it. 

[KevinH]

Ooops. I made what could have seemd a strange comment in here.
Sorry if anyone saw it and wondered what I was on today.
Removed by self-moderation.

[krsilber]

Ooops. I made what could have seemd a strange comment in here.
Sorry if anyone saw it and wondered what I was on today.
Removed by self-moderation.

Been there, done that!!!

I don't think anybody is going to be able to add much that will shed any more light on how this piece was made, unless someone is able to identify the maker and then we can ask them how they did it.

Aha!   So you don't know how it was done!   Who's to say I'm overcomplicating things then?

It was marvered just as much as the other trails, otherwise it would be raised from the surface of the vase.

  Just for argument's sake, how do you know it wasn't?  The base was ground down.

they look like crystals that have been grown out like on pottery with the crystalline glaze. I wonder if there is some way to glaze a glass piece and bake it for the required amount of time?

I've never heard of putting glaze on glass, but since you mention it, I'm going to be brave and bring up an idea that occurred to me before but I didn't dare seriously raise - that it's actually ceramic.  Seems unlikely, I know, but not impossible.  The brown on the interior is one thing that suggests it, since it's common to glaze the inside of ceramic vessels to combat porosity; why (and how) would you do that with glass?  On the other hand, why have a ground circle on the bottom of a ceramic piece?

I've a feeling this topic is getting a bit stale :ac1:, so I won't belabor it any longer.  However, it brings another generally applicable question to mind - when thick trails are marvered in, does it ever create a pattern of raised areas on the inside where the trails are?