Glass Message Board
Glass Identification - Post here for all ID requests => Glass Paperweights => Topic started by: TanToday on November 04, 2013, 10:33:12 PM
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Recent acquisition from a Boston collector, he thought it was one of the older English makers. As my expertise is more with the moderns, I thought it would be useful to ask for opinions on origin from this group. Thanks.
Size is: 3" or 77mm wide x 2" or 52mm tall. Weight is 509 gr or 17.94 oz.
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Rough pontil breakoff.
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Looks to be Richardson to me.
Nick
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I also collect American Brilliant Cut Glass, {ABCG} and one of the tests we use to authenticate old glass {1875-1910} is the blacklight fluorescent test. I just tested and got a greenish hue that indicates manganese in the glass, dating it to that time period. After 1915, this isn't present and no green shows.
Here is the "test" from a ABCG publication:
["The most promising test for detecting counterfeit ware is use of a long-wave, 15 watt Blacklight-Blue Fluorescent Bulb in a dark room. Due to addition of manganese in old glass ingredients to neutralize iron (found in the sand), which caused a greenish cast to the blank, the glass fluoresces a soft yellow-green color, while modern glass glows pink or slightly purple. "]
I also computed the SPECIFIC GRAVITY on the weight, and came up with 2.75-2.85 range. I need to invest in a more accurate calibrated beaker I guess now that I know to test for SG as well.
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The UV test may apply to ABCG but it is not relevant in other glass in the same way (though it can indicate older or newer for products from a given company), as manganese was in common use well into the second half of the 20th C when its use declined for cost reasons and health and safety concerns. It is still found in modern glass from countries where it is relatively cheap
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Hi.
It is certainly Old English, but if the SG is really that low it will not be Richardson. That said, you do need to be very accurate when computing SG if you are trying to measure displaced volume using a calibrated beaker - it is very difficult to get reproducible results. A better way is to measure the weight of the piece in air and immersed in water.
Some of the canes look like Richardson ones, but they style resembles a small group of very neat Old English weights from an as yet unidentified factory (I have posted images of some of these on GMB before). There are two shown at the bottom of the page on my website about Old English paperweights Old English Paperweight Identification (http://www.pwts.co.uk/pages/OE%20Identification.htm).
Alan
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Alan, I carefully reread your treatise on the OE weights. I ordered a digital hanging scale to use the "hanging in water' method of computing SG. That should be here Friday. Previously I was using the "water displacement" with a less than accurate beaker.
In the meantime, I *carefully* re-examined the canes and found the mysterious "rouge cane" that you listed in the OE1 series of weights. Note in picture below.
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Confirming SG computed with a brand new, very accurate hanging digital scale using the water displacement method.
SG = 2.84
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Hi. That SG is very low for Old English, but would just qualify as lead crystal (there is a chart of some of my results accessible from my website Old English page).
The two images I referred two of broadly similar paperweights to yours both have an SG of 3.12 and 3.09 - significantly different from yours, so maybe not the same maker?
Alan