COE compatablity check with magnifying glass?

[Dog Squeez]

Went to The Atlanta Glass Art Guild (AGAG) meeting yesterday and one of the
members said an acquaintance of her's said she knew someone who could tell
if two glasses were compatable just by looking at them through a magnifying
glass. The unanimous opinion was Bullshit but maybe, stranger things are
possible. Just thought I'd post to see if anyone here has heard of this?

[Chris Juedemann]

No.

Chris

[10FennyGlass]

right..., hehe who knows
a witch
a witch

which witch is wich, wait..., i suck

[Greymatter Glass]

hrm.... tough one....

my gut says no, you can't tell by looking, no matter how close you look...

but then, maybe there's something about the way glasses break, or maybe there's something in the magnifying glass that's polorizing the light... but still that wouldn't work.

Argh... I dunno, without more proof / details I think someone was pullin' yer leg.

-Doug

[vetropod]

Maybe she wasn't listening very closely, and the person said that they had such good eyes, that they could look at a pull-test under a magnifying glass and see the most minute bend in the glass? Dunno...


.

[smutboy420]

my gut says no, you can't tell by looking, no matter how close you look...
but then, maybe there's something about the way glasses break, or maybe there's something in the magnifying glass that's polarizing the light... but still that wouldn't work.

I'm going to say IF and just IF they can tell the difference. Lets just say The person has the ability to do it.
I'd have to guess if it is doable it has to do with some thing like the lens polarizing the light some how. when held up to the round rod. like 2 lenses. But it still seems like if it worked at all it can only tell if 2 samples where the same glass or not the same glass. But most likely not what type of glass it was or any thing.
So they might not be able to tell what the c.o.e. is but they might be able to tell they are not the same c.o.e.'s
I have heard of the index of refraction being different on hard glass then soft glass and if stick it in a glass of water they are both supposed to have dif. angels of bend when you look at them in the water.
but I have not been able to quantify that for my self yet because I dont have any clear soft glass rods to do my own test.
So maybe IF the person is able to tell if one glass is some how different from the other that it has some thing to do with that if its doable at all.
but I wonder how it would work using 2 different brands of hard glass next to each other?
I know I can tell the difference between different brands of hard glass (to some degree at least) from looking down the length of a rod or a tube and seeing if its more blue or if its more green or more clear.

[J Howard]

you have to at least bite off a little and give it a chew... soft glass tastes more like flux

[smutboy420]

bite off a little and give it a chew
hot or cold?

R'rrrrr Thats hardcore.

[Dog Squeez]

Every one at the meeting thought it was BS, just thought I'd throw it out here and
see what happened.

[borofreak]

i do not know about magnification but a quick way to identify boro is to mix 16 parts methyl alcohol and 84 parts benzene. you have now created a liquid with the same refractive index as borosilicate, 1.474 Stick glass rod or tube in the jar and the submerged portion will become practicly invisible your soft glass will still be visible unless it has the same r.i.

[FredLight]

Yea, and that bit about having different angles underwater is umm...say, not true. The water causes the glass rods to look bent not the glass. Think about it.