Topic: Hand blown posy vases with vermicular collars

[neil53]

Hi, I've been told that this pair of hand blown posy vases may be Whitefriars from the early 20th century but I can't find anything like them in the published catalogues.  They have trefoil rims, a vermicular collar and are lightly ribbed without wrythening.  The pontil marks are rough.  Has anyone any idea where I might start to look for a maker if not Whitefriars?  I believe that they are made from lead glass but can't confirm it until my new UV light arrives.

Thanks in anticipation, Neil

[Lustrousstone]

Your UV light won't tell you if they are lead crystal; the weight and any ring should do that. Your UV light will tell you that they contain UV as a decoloriser (dull greenish glow), as can be seen from the greyish/purplish tint. Late 19th C looks more likely but finding a maker may be very difficult. They may not even be English

[neil53]

Hi, I have been reliably informed that lead glass will look different under UV light than soda glass or potash glass.  It is easy to distinguish soda glass from lead glass by weight etc. but less so with potash glass which can be as heavy.  It is difficult to tell the difference especially when the glass is blown thin.  As potash glass is unusual in the UK it would help me to establish if certain pieces were made in this country (UK) or abroad.

If I am wrong in this then please let me know as I've otherwise wasted £30.00!!

[glassobsessed]

Your UV light will tell you that they contain UV as a decoloriser (dull greenish glow), as can be seen from the greyish/purplish tint.

Typo from Christine, I think that should read as ...contain manganese as a decolouriser...

I am afraid your reliable informant was not reliable in this case.

John

[Lustrousstone]

Yes typing in a hurry as usual, sorry. It might if you have bought the right wavelength torch. An ordinary UV torch gives a bluish glow with some lead crystal but not all

[oldglassman]

 Sorry 

   I have to disagree, a Shortwave UV lamp is commonly used with antique glass to assertain if contains Lead or not ,with a short wave lamp even if maganese has been used as a decolourizer lead glass will fluoresce bright white with a blue tinge around the  bowl rim or foot rim , a non lead glass . soda/potash will fluoresce greenish yellow again especially around the bowl and foot rim .
  attached are 3 photos which clearly show the results with lead and non lead glass. 1st is a lead glass c 1700 2nd a lead glass c 1690 and a non lead glass c 1680  3rd the foot rim of the non lead glass .

cheers ,
              Peter.

[neil53]

Hi Peter,

I'm sure you are right and happenstance my UV light arrived today.  I'll test it out this evening and report back via this forum as to my results.  I just wish I had some 17th century glasses like yours to test it on.     18th century glasses will have to do.

My reading of all the above is that collectors of 20th century glass are probably looking for some different results from the use of a UV light than collectors of Georgian (or Queen Anne) glass.

Best wishes
Neil

[Lustrousstone]

I just tried again with my UV tube and a bit more time. With my modern (20th) lead glass there is a bluish white glow, but some give a better glow than others, which doesn't necessarily equate to quality (some cheap glasses glow more that expensive ones). Perhaps that just means different lead concentrations

Interestingly, this one, which I believe is the oldest glass I have
http://lustrousstone.co.uk/cpg/displayimage.php?pid=969
http://lustrousstone.co.uk/cpg/displayimage.php?pid=970
glows a distinctly bluish yellowish green - quite different from the lead crystal and the manganese-containing Victorian soda glass

[oldglassman]

 'I'll test it out this evening and report back via this forum as to my results.'


   And your results were ?

   cheers ,
                Peter.

[neil53]

Hi Peter,

Sorry, I received the UV light but not the goggles, and didn't want to use it without protection.  Hopefully I'll be able to do it this weekend and report back, but I can't believe it will do anything other than confrm your input. 

Neil