Glass Message Board

Glass Identification - Post here for all ID requests => Glass => Topic started by: Repz on December 23, 2014, 10:51:08 PM

Title: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 23, 2014, 10:51:08 PM
Can anyone help identify this?

Please see photos.

:-D

PS: I have no idea whatsoever how to attach more than one photo. I took six.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 23, 2014, 10:57:35 PM
Here's the underside:

BTW it weighs 681g.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 23, 2014, 11:11:59 PM
And finally, a top-to-toe shot:

(Also, the white flecks are NOT rough when they break the surface - they can't be detected by touch alone.)
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Lustrousstone on December 24, 2014, 08:54:19 AM
Welcome to the board. To attach more than one picture, just click the more attachments link under the attachments box. Can't help you with who made your obelisk but the flecks look like mica
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 24, 2014, 12:01:59 PM
Thanks and thanks.

So it could just be a student's practice piece that is literally green glass mixed with mica and shaped into an obelisk?
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Lustrousstone on December 24, 2014, 01:29:26 PM
Most things are NOT student pieces. I'm not sure why it would be. Are the sides cut or moulded?
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 25, 2014, 01:57:07 PM
Certainly cut and then gently blunted/worked so the edges are not sharp. Like I say, it isn't completely symmetrical - from some angles it appears to lean to one side or the other. I like it as a paperweight. There are two (2) tiny - and I really do mean tiny - nicks on two corners that only become apparent when viewing it closely for a long time. It is basically in perfect condition.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 25, 2014, 02:01:33 PM
Actually I don't know about the sides - they are highly polished and glossy.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Paul S. on December 25, 2014, 05:00:44 PM
many pressed glass surfaces appear shiny and polished, and was this ability to mimic cut glass that brought into being much of the trade in pressed glass in the middle of the C19 - although the sharp 'edges' of true cut glass probably always defeated the makers of moulded work.
The sharp edges of cut glass were lost after the 1920's as a result of acid polishing which was a more economical and rapid method of removing grinding marks.            Run your fingers over a piece of mid C20 cut glass and the smoothness is very apparent, usually.

The intersection of two flat surfaces - form an arris - or edge as you say, and on older glass these raised features are vulnerable to damage although far less so the newer the piece.

If you can get alight source to provide a raking effect on the sides, and get your eyes really close (or use a loupe) you should be able to assess whether this is pressed or cut.
If cut, then you should see, albeit faintly, the shadowy remains of grinding marks  -  the merest hint of lines running at ninety degrees to the axis of the obelisk  -  if pressed then no matter how close you look you will never find even a hint of these lines.

If the inclusions are mica, then under a decent light individually they should give a hint of sparkle, especially as mica flecks usually show flat planes  -  according to Wiki the word mica is derived from the Latin word, mica, meaning a crumb, and probably influenced by micare, to glitter.
If the inclusions are a dull white, then not really sure what they'd be  -  sorry. :)

Now off for more chocolates, beer and tv.    merry Christmas all.  ;D
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 25, 2014, 10:38:26 PM
Well, handling it and examining it (with untrained eyes) under a desk lamp for several minutes, I think that it is probably an emerald of some sort and that it would make a nice murder weapon. The flecks don't sparkle and there are many parallel 'grinding' lines within the emerald. And what about these bubbles? What would a glasserometrist have to say about those?
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Ivo on December 26, 2014, 07:55:44 AM
Mexican quartz glass is another possibility.  They use panel cutting to high standards. But I must admit, I have never seen any with inclusions.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 26, 2014, 11:46:15 AM
I picked it up for a nominal fee on eBay a year or two ago - basically just paid postage.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: rosieposie on December 26, 2014, 01:37:23 PM
A gemologist should be able to use a spectrometer to tell you if this is glass or a cut gemstone.  It does look very much like glass to me,  but many semi precious gemstones have been carved and sold on eBay as glass, and vice versa.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 26, 2014, 05:51:18 PM
A gemologist should be able to use a spectrometer to tell you if this is glass or a cut gemstone.  It does look very much like glass to me,  but many semi precious gemstones have been carved and sold on eBay as glass, and vice versa.

This all sounds very expensive...

Seriously, I would really like to know exactly what it is or roughly what it is and what the inclusions are. I don't care about what it's worth - particularly - I just have an enquiring mind.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 26, 2014, 05:53:13 PM
I'm - I was - a chemist.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: pamela on December 26, 2014, 06:55:33 PM
With its bubbles inside I would definitely rule out precious or semi-precious stone. As a chemist, you certainly have considered and ruled out any resin material? 
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: rosieposie on December 26, 2014, 07:09:45 PM
Not expensive at all Repz.... if you go into a decent Jewellers and ask them to run it by their spectrometer, they should take it into the back of the shop and put it under the spectro for you.  I bought a box of 'stones' at a bootfair because there was a piece that looked like yellow glass and I took it into our local (Surrey at the time) jewellers and they put it through their spectro and declared it was gem quality Citrine, I seem to remember they simply asked me to put a donation into the Barnardoes collection box they had on the counter.

However if you can definately see air bubbles in it,  then you have already ruled out natural stone and this does sound like glass.

Hello Pamela, looks like our messages crossed in the airwaves. :)
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Paul S. on December 26, 2014, 08:06:10 PM
bearing in mind comments about nominal fee cost, is it worth considering that this is simply some ultra cheap type of bottle glass with masses of inclusions which are usually described as 'seeds or stones' and quite often this whitish/grey colour.               Such low grade glass is frequently this greenish colour owing to the iron impurities in the sand and with non-silica debris that doesn't melt at the same temp. as the sand.            This 'bottle' type glass would probably also be more inclined to contain bubbles than refined glass.         Just a thought.
Might see if you can scratch your name on a window pane to test the hardness of this material  -  quartz should be 7 on the Mohs scale, I think.

Of course if you really want to determine the nature of the inclusions then break the obelisk and take some of the whitish 'crumbs' to another chemist. ;) ;)   

 
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on December 27, 2014, 04:29:30 PM
bearing in mind comments about nominal fee cost, is it worth considering that this is simply some ultra cheap type of bottle glass with masses of inclusions which are usually described as 'seeds or stones' and quite often this whitish/grey colour.               Such low grade glass is frequently this greenish colour owing to the iron impurities in the sand and with non-silica debris that doesn't melt at the same temp. as the sand.            This 'bottle' type glass would probably also be more inclined to contain bubbles than refined glass.         Just a thought.
Might see if you can scratch your name on a window pane to test the hardness of this material  -  quartz should be 7 on the Mohs scale, I think.

Of course if you really want to determine the nature of the inclusions then break the obelisk and take some of the whitish 'crumbs' to another chemist. ;) ;)

Thanks. That seems pretty convincing. I worked as an organic chemist for Big Pharma so this is not my area, as such.
Title: Re: Asymmetric, white-flecked, green glass obelisk - 188mm tall - no markings
Post by: Repz on May 13, 2015, 01:53:24 PM
many pressed glass surfaces appear shiny and polished, and was this ability to mimic cut glass that brought into being much of the trade in pressed glass in the middle of the C19 - although the sharp 'edges' of true cut glass probably always defeated the makers of moulded work.
The sharp edges of cut glass were lost after the 1920's as a result of acid polishing which was a more economical and rapid method of removing grinding marks.            Run your fingers over a piece of mid C20 cut glass and the smoothness is very apparent, usually.

The intersection of two flat surfaces - form an arris - or edge as you say, and on older glass these raised features are vulnerable to damage although far less so the newer the piece.

If you can get alight source to provide a raking effect on the sides, and get your eyes really close (or use a loupe) you should be able to assess whether this is pressed or cut.
If cut, then you should see, albeit faintly, the shadowy remains of grinding marks  -  the merest hint of lines running at ninety degrees to the axis of the obelisk  -  if pressed then no matter how close you look you will never find even a hint of these lines.

If the inclusions are mica, then under a decent light individually they should give a hint of sparkle, especially as mica flecks usually show flat planes  -  according to Wiki the word mica is derived from the Latin word, mica, meaning a crumb, and probably influenced by micare, to glitter.
If the inclusions are a dull white, then not really sure what they'd be  -  sorry. :)

Now off for more chocolates, beer and tv.    merry Christmas all.  ;D

Thanks, I now know my arris from my elbow. As an update, I have lost the blasted thing now, but if and when I find it, I'll take it to a jewellers for them to zap so they can tell me what exactly it is. Hope you enjoyed your beer and chocolates. And a belated HNY to everyone else who contributed to this thread.