I have an embossed Watkins Trial Mark bottle that is purple. It has seams running through the top, a double collar at the top, and a trademark on the bottom that is an I in a diamond. The I/diamond mark is inside a larger circle with rather rough edges...sort of pleated along the edges and distorted...with no additional dating numbers/letters. It is the 8.25" tall, 3" wide, 1.75" thick flask or rectangular bottle. There is no paper label or other markings on the bottle.
From the research I've done online, the trademark is for Illinois Glass and the bottle was probably made on an Owens bottle making machine. I've seen various dates for the I/diamond mark that say it was used in the 20's, but one site said it was used from 1915 to 1929. The bottle is a deep purple, not a light purple, and there is some iridescense on the inside which I think must be from being buried. I thought the bottle was probably an old "manganese" glass bottle that turned purple from extended sun exposure. However, I've read online that manganese was used as a decolorizing agent in glass only until about 1915. In other words, unless the I/Diamond mark really WAS used as early (or earlier) as 1915 it is unlikely that it would appear on a sun colored purple bottle.
I bought the bottle...simply for its deep purple color...at a 2nd hand store. They said it was not an old bottle, "probably only about 40 or 50 years old". It was only $2. I have been unable to find ANY reference to a PURPLE Watkins bottle anywhere online. I have read...repeatedly...that Watkins bottles are common and not worth anything, and also that old manganese glass is sometimes irradiated to make it turn darker purple or turn purple more quickly and that this ALSO devalues sun 'purpled' glass.
I haven't found any mention of modern purple Watkins bottles (I know they still use a Trial Mark bottle), or of reproduction Watkins bottles...particularly purple ones. But the implication is also that it would be unusual to have the I/Diamond trademark on a bottle made of glass that was decolorized with manganese. I don't CARE if it is valuable or rare, I'd just like to know that it is "old". 1915 or even 1920something is old, to ME. Can anyone help date this bottle, or give me better information on the when they stopped using manganese in glass to decolorize it, or if there if there were utilitarian bottles, like Watkins bottles, that were purposely colored purple (not sun colored) and when those were made. Thanks very much.
From the research I've done online, the trademark is for Illinois Glass and the bottle was probably made on an Owens bottle making machine. I've seen various dates for the I/diamond mark that say it was used in the 20's, but one site said it was used from 1915 to 1929. The bottle is a deep purple, not a light purple, and there is some iridescense on the inside which I think must be from being buried. I thought the bottle was probably an old "manganese" glass bottle that turned purple from extended sun exposure. However, I've read online that manganese was used as a decolorizing agent in glass only until about 1915. In other words, unless the I/Diamond mark really WAS used as early (or earlier) as 1915 it is unlikely that it would appear on a sun colored purple bottle.
I bought the bottle...simply for its deep purple color...at a 2nd hand store. They said it was not an old bottle, "probably only about 40 or 50 years old". It was only $2. I have been unable to find ANY reference to a PURPLE Watkins bottle anywhere online. I have read...repeatedly...that Watkins bottles are common and not worth anything, and also that old manganese glass is sometimes irradiated to make it turn darker purple or turn purple more quickly and that this ALSO devalues sun 'purpled' glass.
I haven't found any mention of modern purple Watkins bottles (I know they still use a Trial Mark bottle), or of reproduction Watkins bottles...particularly purple ones. But the implication is also that it would be unusual to have the I/Diamond trademark on a bottle made of glass that was decolorized with manganese. I don't CARE if it is valuable or rare, I'd just like to know that it is "old". 1915 or even 1920something is old, to ME. Can anyone help date this bottle, or give me better information on the when they stopped using manganese in glass to decolorize it, or if there if there were utilitarian bottles, like Watkins bottles, that were purposely colored purple (not sun colored) and when those were made. Thanks very much.
