Topic: Your favourite glass -discussion topic - please join :)

[flying free]

In reference to a piece I posted in another thread I thought I'd start this one

My favourite pieces of glass are those that change colour as it happens.  I'm fascinated by what drove the glass makers to make something like this. Or was it an beautiful accident?

So to start, these are mine:

1) The Lycurgus cup:
The most famous piece that turns red being here:
https://www.britishmuseum.org/collection/object/H_1958-1202-1

Lycurgus cup.

Detailed information, fascinating reading, on it here:  Source -
The Lycurgus Cup –
A Roman
Nanotechnology
Ian Freestone1, Nigel Meeks2,Margaret Sax2 and Catherine Higgitt2
1 Cardiff School of History and Archaeology, Cardiff
University, Cardiff CF10 3EU, Wales UK
2 Department of Conservation, Documentation and
Science, The British Museum, London WC1B 3DG, UK

http://master-mcn.u-strasbg.fr/wp-content/uploads/2015/09/lycurgus.pdf

2)  I have a piece of dichroic glass, a bowl, from before 1707 that is baby blue, but turns orange with light behind it and at a certain position goes completely clear colourless transparent. 

3) Webb's Alexandrite glass - the most fabulous colours created by reheating the glass at a certain point in the making:

https://www.cmog.org/artwork/alexandrite-vase

https://issuu.com/jammdesign/docs/15._fieldings_april_2012/28

4) Gorge de Pigeon pink glass:
https://madparis.fr/IMG/arton5544.jpg

5) Stevens and Williams Silveria - I live in hope of finding one of these one day
https://www.bonhams.com/auctions/25085/lot/305/

m

[Fuhrman Glass]

I think a lot of the early glass was developed by Alchemists and they were experimenting with all types and combinations of elements and chemicals. Some of the early formulas that I have seen have had all different types of additives that in some cases are still difficult to understand what they really were. The use of silver in many of those glass formulas produced all different types of results and the experimentation continues as we speak.
I just saw a program on TV explaining that they have found another example of a Diatetrus cup in Spain but from about the 4th century when the Romans were there. It was discovered in an archeological dig.
A lot of experimentation is now being hampered by the availability of raw chemicals to any but government laboratories. Cadmium for instance has been heavily restricted by the European Union and has changed color formulations not just for glass companies but for manufacturers of paint pigments. Many white formulations used arsenic as a colorant but it has now been heavily restricted in it's use.
This may hamper  the production of reproductions but does restrict the development of new colorations.

[flying free]

Thank you for the detailed and interesting information

I think that's one of the reasons why the area of my greatest interest is early 1800s Bohemian glass (and some French).  The way the houses were all developing their own colours etc. I find it so fascinating. That and the fact that because of the restrictions and because they are two hundred years old now, we are never going to come across that glass again.
Having said that I also collect 1930s glass (multicoloured, intercalaire layered glass etc) and  am really interested in studio glass from the 60s onwards.  So a bit of a spread.  But it's interesting the comparative difficulty in producing colours and effects now to then, because of a restriction on materials use.

m

[chopin-liszt]

I'm really interested in this thread, but it's too difficult and wide a question for me to be able to come up with anything specific.
I am fascinated by the interactions of heat, glass and silver.
I nearly managed to have a conversation with a glassmaker who concentrated on that once, but I got dragged away.
But this does have a lot in common with what M is talking about - when the makers made their own colours, often with really dangerous chemicals and the attendant lack of safety elves.