Glass Message Board
Glass Identification - Post here for all ID requests => Glass => Unresolved Glass Queries => Topic started by: ruth on September 10, 2005, 09:50:30 PM
-
Two clear and orange pieces I have no idea about.
Hyacinth vase
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-1825
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-1824
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-1823
I would particularly like to know how the orange was created. [ Looks like crystals growing in the top part, last pic shows].
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-1822
http://glassgallery.yobunny.org.uk/displayimage.php?pos=-1821
And for other new users, I have discovered the joys of resizing pics using Fastone image viewer [freeware] before using Tinypic. It is much quicker.
Now will login :idea:
-
The orange is probably marvered enamels, them reheated and then cooled suddenly. How thie crazing was limited just to the orange I don't know. Perhaps they used a very fast dip in water or a blast of compressed air.
-
How thie crazing was limited just to the orange I don't know. Perhaps they used a very fast dip in water or a blast of compressed air.
Good morning Frank
I think it was in one of your newsletters that I received back in the 90's that was discussing why Monart, and similar glass, had a tendency to suffer stress cracking. From memory, and this what I have quoted in the past, it is due to the different chemical composition of the individual colours cooling down at different speeds....and if I recall correctly it is those that cool first that are the ones most subject to "crack" due to their set state being much more influenced by the movement of the still maleable components............ or perhaps I was dreaming....... anyway if it wasn't you it was damn near your twin :wink: Which of course made me wonder if this is what happened with this piece.
Regards
Gareth
Morgan48
-
The Monart cloissone effect was achieved by dipping in a bucket of water and then blowing up to widen the cracks.
Crackling effects are done in the same way but have a different effect.
The stress cracks in Monart are due more to poor annealing than to co-efficient problems. These are faults not decoration techniques.
The orange vase here has a deliberate decoration effect and while it is certainly achieved by causing a difference in expansion, exactly how it was achieved is not clear. There is also a technique called stretching that exploits different temperatures of the layers to achieve another similar effect.
Whatever, theere are as many different ways of exploiting glass decoration during the making and many are developed by particular glassworks - perhaps because they saw the effect and found their own way of doing it.
-
The stress cracks in Monart are due more to poor annealing than to co-efficient problems. These are faults not decoration techniques.
.
Hi Frank
Understood............... What I was just wondering was wether or not glassmakers once having understood the various reactions, albeit they might be classed initially at some stage as "faults". would then exploit and attempt to control these to produce "decorative" effects.....a recreation of the divine accident as it were...... but then maybe that is one of the points you are making. The reference to Monart however was more by association rather than being the best available example.
Regards
Gareth
Morgan48
-
Unlikely, as the result of coefficient differences is cracks in one or more layers of glass. As Monart only used the thinnest layer of colour they only got the very small cracks.
But some of the workers who made 'frigger' paperweights using Moncrieff's MS1 glass found their creations in pieces after annealing if they attempted to use colours with it.
-
My puzzlement comes from thinking that the top part of the orange looks as though it GREW. Ie had some sort of life! Inorganic of course!
Another try at showing.
http://tinypic.com/dng08k.jpg
http://tinypic.com/dng0aa.jpg
Ruth
-
That is very odd, perhaps it was made by using predecorated 'petals' of glass instead of enamels. Very puzzling but I guess it is dead now :?
-
I think that it is a real woody/fiberous type of plant incased between 2 layers of glass. Don't ask me how they did it- I have no clue. But that is what it looks like to me from the pictures.
-
Re-visiting again, I don't think it could be organic matter as this would just be vapourised and result in bubbles. As Gareth said and I confused the principle cause of this type of effect is movement during cooling due to different thermal qualities. Of course the effect can be exploited by skilled glassmakers.
Perhaps Adam A can give us his thoughts on how these effects can be expolited with destroying the piece.
-
I think that the crackling is caused by an incompatible colour with a different coefficient of expansion from the clear glass and that the petal effect is the result of the colour being applied in a frit or granular form. When stretched in the blowing process these beecome petals.