Author Topic: Sklo Neodymium Paperweight on eBay  (Read 2323 times)

0 Members and 1 Guest are viewing this topic.

Offline glassobsessed

  • Members
  • **
  • Posts: 3985
  • Gender: Male
    • Mdina
    • South Wales
Re: Sklo Neodymium Paperweight on eBay
« Reply #10 on: January 03, 2011, 09:38:24 PM »
Here is an example of one colour change: http://www.glassmessages.com/index.php/topic,29702.msg161109.html#msg161109

Not all shades of neodymium glass are the same, searching the message board will provide lots of examples. I think for your paperweight a close up photo in daylight next to one taken under fluorescent light should be definitive (low energy bulb and turn of the flash).

John


Offline jakgene

  • Members
  • **
  • Posts: 719
  • Gender: Female
  • Mrs Doasyouwouldbedoneby
    • Mid 20 Century glass
    • Australia
Re: Sklo Neodymium Paperweight on eBay
« Reply #11 on: January 04, 2011, 12:42:15 PM »
I have one of these identical paperweights, which I have had from new (in 1969) .  Mine doesn't colour change at all though - I have just checked it against the two types of light which change a piece of caithness neodymium glass from turquoise to lavender, and can see no difference in colour on mine.

Not sure if that clarifies anything for you though....
regards

JAK



jakgene
Western Australia
Mid 20 Century Glass
British Glass, Scandinavian Glass, Murano Glass,
Paperweights. (and anything gorgeous!)


Offline marie anne

  • Members
  • **
  • Posts: 88
Re: Sklo Neodymium Paperweight on eBay
« Reply #12 on: January 04, 2011, 05:34:00 PM »
Hi,
John - I've taken a photo underneath a fluorescent tube and compared it to the daylight photo see below.  Under the tube light the colour is more brown but definitely not blue - is that a definitively no for neodymium then?  That would agree with JAK's observation.  BTW which Caithness design gives you the strong colour change?  I'm on the lookout now for some neodymium glass that I can play around with in different lights, learn from, and use as a comparison for future reference.
Thank you both for your comments.
Marie.


Offline glassobsessed

  • Members
  • **
  • Posts: 3985
  • Gender: Male
    • Mdina
    • South Wales
Re: Sklo Neodymium Paperweight on eBay
« Reply #13 on: January 05, 2011, 10:13:04 AM »
Looks like a no then, which sort of makes sense. Why use neodymium if the colour and or the colour change is hard to see? Nice weight though.

When you do find a bit made of neodymium glass and you take it from daylight into fluorescent light the colour change is immediate and obvious, I almost dropped the lighter in that photo in shock the first time I saw it happen.

John


Offline marie anne

  • Members
  • **
  • Posts: 88
Re: Sklo Neodymium Paperweight on eBay
« Reply #14 on: January 05, 2011, 12:48:55 PM »
Thank you for your reply John.  I love the way your glass changes in your photo.  I'm definitily going to look out for some neodymium glass to play with now.  I like my paperweight and bought it because it was the first czech weight I'd seen.  I mostly buy to sell on but I also love learning about glass and view my purchases as a temporary collection.  I started thinking the weight had a neodymium tint based on a previous thread on glass messages with a similar paperweight.  I'm grateful to everyone who contributed to this current thread.  Thank you for clarifying what I should be seeing with neodymium and which lights to use.
Thanks everyone,
Marie.
 


Offline flying free

  • Members
  • **
  • Posts: 7021
    • UK
Re: Sklo Neodymium Paperweight on eBay
« Reply #15 on: January 05, 2011, 04:50:56 PM »
this is a neodymium paperweight which changes colour but not all of it!  the middle bit stays green and pink, it's only the outer which changes colour.  I didn't put it under a fluorescent light tube but under a long life light bulb.  I'm not quite sure they are the same?
m


Offline glassobsessed

  • Members
  • **
  • Posts: 3985
  • Gender: Male
    • Mdina
    • South Wales
Re: Sklo Neodymium Paperweight on eBay
« Reply #16 on: January 05, 2011, 06:38:37 PM »
They are, the low energy bulbs (with a much longer life than the 'old fashioned' tungsten filament bulbs) are just very small fluorescent tubes, some of today's smaller examples are in the shape of a spiral so that a long tube can be confined in a small space.

You can also get 'light bulbs' which are made with a collection of LEDs (light emitting diodes), these use even less energy than the low energy bulbs but as yet the light given off is not always that bright and tends to be quite 'cold' or harsh.

John


Offline flying free

  • Members
  • **
  • Posts: 7021
    • UK
Re: Sklo Neodymium Paperweight on eBay
« Reply #17 on: January 05, 2011, 11:42:43 PM »
thanks John, well it's not a wonder I hate them then!  I've given up on them except in the childrens rooms where they tend to leave lights on and it's ages before I realise.  I can't stand the light they give off and no one can see what they are doing when we use them.
m


Offline flying free

  • Members
  • **
  • Posts: 7021
    • UK
Re: Sklo Neodymium Paperweight on eBay
« Reply #18 on: January 16, 2011, 10:31:56 PM »
I found this this week - neodymium Jelinek egg - it is in fact paler than the long life photo even but my camera wants to make it darker for some reason  :-\
It's the most amazing shocking pink under normal light.
m


Offline misha

  • Members
  • **
  • Posts: 58
  • Gender: Male
Re: Sklo Neodymium Paperweight on eBay
« Reply #19 on: January 17, 2011, 06:22:22 AM »
They are, the low energy bulbs (with a much longer life than the 'old fashioned' tungsten filament bulbs) are just very small fluorescent tubes, some of today's smaller examples are in the shape of a spiral so that a long tube can be confined in a small space.

You can also get 'light bulbs' which are made with a collection of LEDs (light emitting diodes), these use even less energy than the low energy bulbs but as yet the light given off is not always that bright and tends to be quite 'cold' or harsh.

John

Insomuch as this maybe 'off-topic' perhaps a little info re. the types of lamps [correct terminology] may help in understanding what type of lamp will have the effect that helps identify neodymium enriched glass.

For a start the 'bulb' is the glass envelope which contains the internal components that produce light, be that viable or not.
Some lamps don't need a bulb at all. Some need two layers to reduce Ultra Violet radiation and some to actually have visible light produced.

Fluorescent Lamps:
, so named because of a fluorescent effect making visible light from UV production. It's the florescence of a powder lining a primary bulb that does this.
The UV production comes from the flow of electrical current between metal conductors at each end of the bulb of a tubular construction through a gas inside that bulb.
The gas and phosphor used depends on the colour spectrum produced. Some have a 'warm' colour, some have a 'cool' colour which is close to that of daylight. Some are of specific design for biological effects like those used in butches shops and plant growing applications... a mater of light spectrum produced.
In domestic application the 'daylight' type appear to be brighter.
All fluro tubes light output/efficiency drops over usage time. After a full year of use it's sometimes as bad as 50% yet still work.  This happens in all forms of fluro, be it the straight long fat tubes or the compact spiral or looped type.
Your 'screw' or 'bayonet' domestic lamps that replace older incandescent lamps are correctly termed 'Compact Fluorescent Lamps'  [CFL]
They are available in large sizes [wattage] now of equal size and output to a comparable small/medium rated straight tube. If they are too dim buy the largest you can.
Frankly, these types of lamp are old technology going nowhere. The CFL suffer badly from rapid switching and a buildup of heat in some light fittings that reduces their life.
Better lamps will come soon. They will always have their place in certain applications.
This type of lamp is of medium efficiency, producing more lumens/watt than the older standard incandescent lamps.


Incandescent Lamps:
so named due to a wire element inside the bulb which heats to the point of 'incandescence' and so producing visible light.
Some types of this lamp produce a lot of Infra Red radiation and some produce Ultra Violet requiring a secondary bulb to limit that UV output.
Incandescent lamps include the old bog standard lamp you now replace with CFL and also include the 'Halogen' and 'Quartz Iodide' Lamps which are actually the same.
The term 'halogen' comes from the inert class of gas used inside the primary bulb to prevent element burnout. Iodide type gas is of the halide class chemical. Tungsten is the metal used in most incandescent lamps and in the past a carbon filament element has been used... very rare now but looked great in an old traditional light fitting!
The Halogen type come in a variety of forms [globe and tube] and voltages [12V,110V and 240V] that includes a look-a-like bog standard lamp.  These look-a-like type have an internal and an outer bulb. They are marketed as being 'energy saver' which is an absolute sham/scam because they produce near 50% heat instead of visible light. They may produce more lumen/watt however that is due to the incandescent element glowing far hotter than a standard type. Many small halogen lamps are used in 'down light fittings' and have been the principal cause of house fires when installed incorrectly with regard to heat build-up.  Incorrectly installed roof insulation combined with this also is a huge fire hazard. Sadly insulation install has been incorrectly blamed for house fires here in Australia based purely on malicious political argument. [fact is house fires in insulated homes dropped, but that fact wasn't a biased media friendly fact]
The incandescent lamp will always have it's place in certain applications like oven lamps where heat affects other types. 
These types of lamp are of low efficiency despite the rhetoric of some manufactures/suppliers. The Halogen have a very low life span indeed.... not cost efficient at all.

Light Emitting Diode [LED] Lamps: so called due to being an electronic component that emits certain spectrum light.
These can be in the range of IR, all specific and combined visible light colours and UV.  Your CD & DVD drive uses IR laser LED... your penlight UV torch uses LED... your 'BlueRay player uses both IR & UV laser LED.
These have been widely used in industrial applications for control panel indicators for years. Used in car dashboards these days too. They outlast the small incandescent type which is important for critical monitoring of a machine status.... a blown globe doesn't indicate anything! 
In a domestic lighting application they are currently being used in clusters. They require no glass bulb at all, run very cool and can be spectrum specific depending on application.
Direct consumer voltage [110v or 240V] lamps are available as well as the form to suit a lamp fitting. High output clusters are used for street lighting today.
Currently there is technology in this field which is of far higher light output than the standard LED used in domestic lamps. The manufactures of such high output LED are using them in pocket torches currently instead of domestic applications because that is where they can make the most money selling fancy toys rather than an item that benefits the wider community. Current lamps have some problems that can be addressed by the use of dispersive lenses and wider focus. Colour output can be highly manipulated and controlled. [How many colours do you see on your High Definition LED TV?]
This IS the future of domestic lighting you children will use in the future long after those profit driven manufactures are dead. In some applications they cannot be used due to destruction from heat in the environment they are used [ovens by example]
This type of lamp is of high to very high efficiency. 

With regard to the apparent colour change of neodymium glass, if a specific spectrum fluro tube can have this affect an LED can also have the same affect if 'tuned' to correct light frequency.

With regard to the fluorescence of Uranium glass by UV from a 'fluro tube' [misnomer as they are really a discharge tube with no phosphor] an UV output LED sure has that same affect.
As mentioned previously in this thread, an incandescent lamp will not due to the wide spectrum output and minimal UV content. 

 

Search
eBay.com
eBay.co.uk

Link to Glass Encyclopedia
Link to Glass Museum
Enter
key words
to search
Amazon.com