Purple glass - nuking- sun exposure?
- Thread starter MiamiMaritime
- Start date
Welcome to our Antique Bottle community
Be a part of something great, join today!
sscokebottles
Well-Known Member
Holy crap I hate that dude. He basically takes an unembossed soda bottle worth maybe a dollar or two, slaps a fake 1900's diamond Coca-Cola label on it, and sells it for $100+. He does the same thing with with original straight sided cokes and sells them for almost 5X what they are actually worth. I even remember one time he had an unembossed hutch, put on one of his famous coke labels on it, and sold it for like $500 as an "EXTREMELY RARE COCA-COLA HUTCH WITH LABEL". People can be so stupid sometimes.
MiamiMaritime
Well-Known Member
Will my bottles turn a little purple if they are in a window 30-40 years?
cyberdigger
Well-Known Member
Yes, even yours will if they are exposed to sunlight and they were made with manganese.
zecritr
Well-Known Member
lol I would say yes there are more honest ways to get it done faster.there is a very good thread here on this very topic around here someplace lol
guess some people don't like rip-offs(be nice to nuke them),
they should be light to medium purple/Amethyst,is my understanding
guess some people don't like rip-offs(be nice to nuke them),
they should be light to medium purple/Amethyst,is my understanding
epackage
Well-Known Member
From a few different sites....
Has all "sun-purpled" glass turned that color by the sun?
In a word (or 2) "ABSOLUTELY NOT"! It is most often turned purple by putting it in a box for a few weeks under a lamp which was intended to kill germs by ultraviolet radiation. That is why we have "sun-purpled" in quotation marks. **
Does all old glass naturally turn purple in the sun?
Some does and some doesn't. It depends on what the meaning of "old" is and what the glass formula is. Some will tint slightly if stored near a sunny window and this is regarded by antique glass folks as "discoloration". All discolored antique glass is devalued which is why it is advisable to not store old glass where the rays from the sun can adversely affect it.
Is "sun-purpled" glass a good investment?
On the contrary, it is tantamount to purchasing a piece of damaged glass and the value is decreased as though it had a serious crack or chip.
Why is clear Early American Pattern Glass being turned artificially purple?
Because presumably the people who turn it purple don't respect history or care that they are ruining an historical artifact & the people buying it don't know that they are purchasing a formerly valuable, but now worthless, antique.
I'm told that the process of turning antique glass purple is not an important issue because the process is reversible by reheating the glass. So what's the big deal?
Unfortunately your source for that information is not alone in believing that but is DEAD WRONG. Hundreds of folks have made that claim to us but not ONE has ever demonstrated a successful reversal to the original state of the Early American Pattern Glass. If you believe you will be the first, please properly document your effort and let us know. EMAIL US
PS We actually have had one response to this challenge which claimed to have successfully turned sun-purpled glass beads back perfectly clear.... at which point they were totally melted.....
[align=center]One of the sad consequences is the incidence of fraudulently advertised "new" colors of a pattern. Collectors have been known to purchase what they are told is a newly discovered color in their pattern and find after having paid a premium price for it that it has simply been "nuked".[/align][align=center] [/align][align=center]
[/align][align=center] [/align][align=center]
Colorless glass is not always, or even usually, absolutely colorless. It will usually have very faint tints of pink or "amethystine" (faintly visible in the base of the bottle to the left), amber or "straw", grayish green, grayish blue, or grey. These faint colors are viewed easiest when looking through the thickest portion of the bottle, i.e., sideways through the base. Colorless glass is usually attained by using the purest sand source possible and by adding "decolorizing agents" to the glass batch to offset the residual iron impurities (Dillon 1958). Common decolorizing agents were manganese dioxide, selenium dioxide (usually in conjunction with cobalt oxide), and arsenious (arsenic) oxide which is also used as a stabilizer of selenium in decolorizing glass - or some combination of these compounds (Trowbridge 1870; Scholes 1952; Tooley 1953; Lockhart 2006a).
Colorless glass actually does have more utility in dating and typing than most other colors, though still of limited application. Some of the better dating reliability is for bottles with manganese dioxide decolorized glass. Upon exposure to sunlight, this glass will turn a light pink or lavender to moderately dark amethyst or purple depending on the amount of manganese and amount of ultraviolet (UV) light. This is called "sun-purpled" or "sun colored amethyst " (SCA) glass. The picture to the right shows a Johnson's Chill and Chill Tonic (Savannah, GA.) manufactured ca. 1900-1915. This bottle began its life as colorless glass and has "turned" a much darker than average color of amethyst due to the exposure to (likely artificial) UV light (Kendrick 1968; Lockhart 2006b). The light lavender tint produced by manganese offsets the green tint of the iron impurities in sand creating a largely colorless glass.
The Venetians apparently discovered by the 15th century that manganese could be used to decolorize glass. Manganese became known as "glassmakers soap" due to the ability to "cleanse" or neutralize the effects of other impurities in the sand, particularly iron (Hunter 1950). Manganese dioxide induced colorless glass was, however, by far most commonly used from the 1880s to about the end of World War 1. At that time manganese dioxide use was greatly reduced for a variety of reasons, although largely because it did not work as well as other chemical decolorizers (see next paragraph) in the open continuous glass tanks used by the increasingly dominant bottle making machines - both semi-automatic and automatic. It is often noted in the literature that the reason for the switch from manganese dioxide to other decolorants was due to the cut-off of German imports to the U. S. during WW1. Although all imports from Germany (and Europe in general) were greatly constricted during this time, Germany was not a significant source of manganese for the U. S., providing only 2% of the imported manganese supplies in 1910 just prior to the war (Kendrick 1964; Lockhart 2006b). It should be noted that occasional manganese dioxide decolorized bottles may date as early as the 1820s or as late as the 1930s (McKearin & Wilson 1978; Giarde 1989; Jones & Sullivan 1989; Lockhart 2006a & b), although the large majority of bottles made with manganese decolorized glass were made between about 1890 and 1920 (empirical observations).
Colorless glass which was de-colorized with selenium or arsenic (or typically a combination of the two in conjunction with cobalt oxide) results in a very faint "straw" or amber tint to the thickest portions of the glass (Scholes 1952; Tooley 1953; Lockhart 2006b). The picture to the left shows this color evident in the thick portion of a milk bottle (underneath the line pointing out the valve mark) that dates from between 1925 and 1930 based on a makers mark for the Pacific Coast Glass Company (Toulouse 1971). Click Cloverdale Dairy Co. to see the entire bottle which was used by a dairy in eastern Nevada. This colorless "color" can be very diagnostic of a machine-made bottle made from about 1912 to 1915 to typically no later than the 1950s (Girade 1989; Lockhart 2006b; empirical observations). The straw tinted colorless glass in bottles does show up frequently in mouth-blown bottles but typically later ones (1900-1920), although can be found occasionally in bottles from the mid-19th century. (Click French mustard bottle to view an 1870s era bottle with a faint straw cast - evident at the heel - to the otherwise colorless glass.) Selenium was the best decolorizer for glass made in open glass tanks (versus the earlier closed pots) which was used with most all automatic bottle machines. Like the colorless manganese dioxide glass, selenium decolorized glass will react slightly to UV light which produces or enhances the straw tint (Scholes 1952; Lockhart 2006a & b).
Diagnostic Utility: Both of the above colorless glass tints can be useful diagnostic tools for an archaeologist who may be dealing with fragmental bottles. One can be quite confident that if the fragment is colorless with a slight straw tint, it very likely is from a machine-made bottle, unlikely to date from much prior to World War 1 (i.e., mid-1910s), and could date as late as the mid-20th century (or later). Conversely, a colorless fragment with a slight amethyst tint is quite likely to date to or prior to World War 1 (1915-1920) and is more likely than not to be from a mouth-blown bottle. Bottles with a grayish tint seem to date between 1915 and 1925, although numerous examples outside that range have been noted by the author (Giarde 1989; empirical observations). Generally speaking, bottles of colorless glass were relatively uncommon prior to the 1870s but became quite common after the wide spread use of automatic bottle machines in the mid to late 1910s (Kendrick 1968; Toulouse 1969a; Fike 1987; U. of U. 1992). Nothing is absolute in these date range estimates, but they are believed to have reasonably high reliability.
As a side note, crown top soda bottles were generally not decolorized with manganese after 1914, giving a good ending date for such "colorless" bottles with an amethyst (manganese dioxide decolorized) cast to the glass as the beginning of World War 1; most of these type bottles would be mouth-blown (Lockhart 2006a & b).[/align]
Has all "sun-purpled" glass turned that color by the sun?
In a word (or 2) "ABSOLUTELY NOT"! It is most often turned purple by putting it in a box for a few weeks under a lamp which was intended to kill germs by ultraviolet radiation. That is why we have "sun-purpled" in quotation marks. **
Does all old glass naturally turn purple in the sun?
Some does and some doesn't. It depends on what the meaning of "old" is and what the glass formula is. Some will tint slightly if stored near a sunny window and this is regarded by antique glass folks as "discoloration". All discolored antique glass is devalued which is why it is advisable to not store old glass where the rays from the sun can adversely affect it.
Is "sun-purpled" glass a good investment?
On the contrary, it is tantamount to purchasing a piece of damaged glass and the value is decreased as though it had a serious crack or chip.
Why is clear Early American Pattern Glass being turned artificially purple?
Because presumably the people who turn it purple don't respect history or care that they are ruining an historical artifact & the people buying it don't know that they are purchasing a formerly valuable, but now worthless, antique.
I'm told that the process of turning antique glass purple is not an important issue because the process is reversible by reheating the glass. So what's the big deal?
Unfortunately your source for that information is not alone in believing that but is DEAD WRONG. Hundreds of folks have made that claim to us but not ONE has ever demonstrated a successful reversal to the original state of the Early American Pattern Glass. If you believe you will be the first, please properly document your effort and let us know. EMAIL US
PS We actually have had one response to this challenge which claimed to have successfully turned sun-purpled glass beads back perfectly clear.... at which point they were totally melted.....
[align=center]One of the sad consequences is the incidence of fraudulently advertised "new" colors of a pattern. Collectors have been known to purchase what they are told is a newly discovered color in their pattern and find after having paid a premium price for it that it has simply been "nuked".[/align][align=center] [/align][align=center]
[/align][align=center] [/align][align=center]
Colorless glass is not always, or even usually, absolutely colorless. It will usually have very faint tints of pink or "amethystine" (faintly visible in the base of the bottle to the left), amber or "straw", grayish green, grayish blue, or grey. These faint colors are viewed easiest when looking through the thickest portion of the bottle, i.e., sideways through the base. Colorless glass is usually attained by using the purest sand source possible and by adding "decolorizing agents" to the glass batch to offset the residual iron impurities (Dillon 1958). Common decolorizing agents were manganese dioxide, selenium dioxide (usually in conjunction with cobalt oxide), and arsenious (arsenic) oxide which is also used as a stabilizer of selenium in decolorizing glass - or some combination of these compounds (Trowbridge 1870; Scholes 1952; Tooley 1953; Lockhart 2006a).
Colorless glass actually does have more utility in dating and typing than most other colors, though still of limited application. Some of the better dating reliability is for bottles with manganese dioxide decolorized glass. Upon exposure to sunlight, this glass will turn a light pink or lavender to moderately dark amethyst or purple depending on the amount of manganese and amount of ultraviolet (UV) light. This is called "sun-purpled" or "sun colored amethyst " (SCA) glass. The picture to the right shows a Johnson's Chill and Chill Tonic (Savannah, GA.) manufactured ca. 1900-1915. This bottle began its life as colorless glass and has "turned" a much darker than average color of amethyst due to the exposure to (likely artificial) UV light (Kendrick 1968; Lockhart 2006b). The light lavender tint produced by manganese offsets the green tint of the iron impurities in sand creating a largely colorless glass. The Venetians apparently discovered by the 15th century that manganese could be used to decolorize glass. Manganese became known as "glassmakers soap" due to the ability to "cleanse" or neutralize the effects of other impurities in the sand, particularly iron (Hunter 1950). Manganese dioxide induced colorless glass was, however, by far most commonly used from the 1880s to about the end of World War 1. At that time manganese dioxide use was greatly reduced for a variety of reasons, although largely because it did not work as well as other chemical decolorizers (see next paragraph) in the open continuous glass tanks used by the increasingly dominant bottle making machines - both semi-automatic and automatic. It is often noted in the literature that the reason for the switch from manganese dioxide to other decolorants was due to the cut-off of German imports to the U. S. during WW1. Although all imports from Germany (and Europe in general) were greatly constricted during this time, Germany was not a significant source of manganese for the U. S., providing only 2% of the imported manganese supplies in 1910 just prior to the war (Kendrick 1964; Lockhart 2006b). It should be noted that occasional manganese dioxide decolorized bottles may date as early as the 1820s or as late as the 1930s (McKearin & Wilson 1978; Giarde 1989; Jones & Sullivan 1989; Lockhart 2006a & b), although the large majority of bottles made with manganese decolorized glass were made between about 1890 and 1920 (empirical observations).
Colorless glass which was de-colorized with selenium or arsenic (or typically a combination of the two in conjunction with cobalt oxide) results in a very faint "straw" or amber tint to the thickest portions of the glass (Scholes 1952; Tooley 1953; Lockhart 2006b). The picture to the left shows this color evident in the thick portion of a milk bottle (underneath the line pointing out the valve mark) that dates from between 1925 and 1930 based on a makers mark for the Pacific Coast Glass Company (Toulouse 1971). Click Cloverdale Dairy Co. to see the entire bottle which was used by a dairy in eastern Nevada. This colorless "color" can be very diagnostic of a machine-made bottle made from about 1912 to 1915 to typically no later than the 1950s (Girade 1989; Lockhart 2006b; empirical observations). The straw tinted colorless glass in bottles does show up frequently in mouth-blown bottles but typically later ones (1900-1920), although can be found occasionally in bottles from the mid-19th century. (Click French mustard bottle to view an 1870s era bottle with a faint straw cast - evident at the heel - to the otherwise colorless glass.) Selenium was the best decolorizer for glass made in open glass tanks (versus the earlier closed pots) which was used with most all automatic bottle machines. Like the colorless manganese dioxide glass, selenium decolorized glass will react slightly to UV light which produces or enhances the straw tint (Scholes 1952; Lockhart 2006a & b). Diagnostic Utility: Both of the above colorless glass tints can be useful diagnostic tools for an archaeologist who may be dealing with fragmental bottles. One can be quite confident that if the fragment is colorless with a slight straw tint, it very likely is from a machine-made bottle, unlikely to date from much prior to World War 1 (i.e., mid-1910s), and could date as late as the mid-20th century (or later). Conversely, a colorless fragment with a slight amethyst tint is quite likely to date to or prior to World War 1 (1915-1920) and is more likely than not to be from a mouth-blown bottle. Bottles with a grayish tint seem to date between 1915 and 1925, although numerous examples outside that range have been noted by the author (Giarde 1989; empirical observations). Generally speaking, bottles of colorless glass were relatively uncommon prior to the 1870s but became quite common after the wide spread use of automatic bottle machines in the mid to late 1910s (Kendrick 1968; Toulouse 1969a; Fike 1987; U. of U. 1992). Nothing is absolute in these date range estimates, but they are believed to have reasonably high reliability.
As a side note, crown top soda bottles were generally not decolorized with manganese after 1914, giving a good ending date for such "colorless" bottles with an amethyst (manganese dioxide decolorized) cast to the glass as the beginning of World War 1; most of these type bottles would be mouth-blown (Lockhart 2006a & b).[/align]
RIBottleguy
Well-Known Member
I like to look at is this way. It's like getting a tan. Nuking a bottle is like going to a tanning salon for a whole day. You come out redder than a lobster (hideous in other words). But, if you patiently work on a natural tan, you can get nice results! The same goes for bottles.
cowseatmaize
Well-Known Member
Most window glass filters or at least alters the UV wavelength. You'll sunburn faster painting the outside trim than you will the inside. [
][]
][]Dragon0421
Well-Known Member
I am a fan myself of the purple colored bottles and have some in my collection. You will have some who will say they are not valuable and are worthless. In my case and point if you look on eBay and other sites on the internet they are selling , there is some inherent value to someone out there. I will put this link up for the ones that have a hard time with the word value or capitalism. I have always been told it is only worth what you can get out of it, or what a person will pay for it. So please check the links below, for some of the forum members that might need the words defined for them. And yes i did good on that auction, just wish i had more time to share info here with the people on the forum.
http://www.thefreedictionary.com/value
http://www.thefreedictionary.com/capitalism
http://www.thefreedictionary.com/value
http://www.thefreedictionary.com/capitalism
Similar threads
Members online
No members online now.
Latest threads
-
-
-
-
Husky beverages bottles. Please help it's been driving me crazy!- Started by Step Back In Time
- Replies: 10
-
-
