Topic: Fractures on the 4 faces of Schrotter's Sklo Bullet Vases?

[Anik R]

... and that's what I call a beautiful answer...   My vase does not have a fault, but an 'essential stray from perfection'. 

I am perfectly satisfied with that. 

Thank you!

[Cathy B]

Over the years, Glen has discussed the different terminologies for the marks to be found on the surface of pressed glass, which have different names depending on how they were formed. They are rarely considered 'flaws' as such. Somewhere there is a post which describes them all, which I can't find off hand, but this thread mentions shear marks (sometimes called straw marks), lap marks and settle waves.

As the mark you're referring to seems to form relatively consistently in the one place, that might suggest a shear mark? I think annealing marks are different again?

[glassobsessed]

Jindrich mentioned that some of the Lens vases are prone to spontaneous cracks developing. The stresses that cause them are a result of the variation in thickness and too rapid cooling of the glass during manufacture.

He had a photo of a cracked jardiniere, it was a real horror show.

John

[px]

He had a photo of a cracked jardiniere, it was a real horror show.

John

Ouch...    I don't like horror shows.  And I love my Vizner lens vase. So I think - and here's a hint for Anik too: Let's not look too closely for our vases once bought.   :pb:
However -  nice to know that in Schrötter lens vase it seems some kind of marks belong there more or less.

[Cathy B]

Hmmm. Here's one thread where John & Jindrich discuss the issue, but I can't find the pic of the jardinier.

http://www.glassmessages.com/index.php/topic,26574.msg146128.html#msg146128

A stress fracture would be considered damage though, wouldn't it, unlike shear and annealing marks?

[glassobsessed]

Sorry Cathy, you were on a wild goose chase looking for the photo on the board.

A stress fracture is serious damage, not as bad as in two or more pieces though......

Mould marks, bubbles, small flaws, etc are often a feature of Sklo Union production, they are to be expected. It was just the way they were made, the finished quality varies widely.

John

[px]

By the way, and idea: it would be nice if someone would have the time to  start a thread and take pictures of these different kinds of flaws one might encounter in glass. The terminology is not always that clear, especially for us who don't have English as the first language.
I mean what does a "chip",  "flea bite" , "mould mark" or "annealing mark" etc look like.
You see them sometimes in ebay ads but still if I know there's a flaw in my vase and I should describe it then it's harder that way.

I think when the object lies on the table in "two or more pieces" wouldn't have to be pictured. 

[Paul S.]

just had a look at my three 'bullets', and they all show, to a greater or lesser extent, these lines which appear to start at the top and run down thru the lens.  Most can be felt on the inside only, but on one example the line can be detected on the outside, just.  They vary from being almost impercetable to blindingly obvious - although on my pieces certainly none is a fracture.   My colours are clear, teal (?) and citrine.   From what I can see, there appears no disturbance of the glass within its thickness.
Think I would have to discount Cathy's comment that these.....'might suggest a shear mark?'   -  but what would help is if someone can state how the internal cavity is produced  -  i.e. piston plunger - compressed air etc., because I feel that is the source of these marks  -  in other words they are being transferred from some part of the moulding process, in this instance.     
John has commented, quite rightly, on the extent of the finish quality on Sko Union pressed glass, and I notice surprisingly that whilst two of mine have the mould seams on opposite corners (as you would expect), my citrine piece appears to have been fire polished to the extend that these have been removed completely.
Nice idea px - to standardize these faults such as flea bites, mould marks etc.etc.. but you're on to a loser - too subjective - can't see people ever agreeing on what might constitute the size of a flea bite or whether something was an annealing mark or something else - just look at ebay     For what it's worth I can see the marks on the amethyst 915/200 piece, and this is typical of how the mark appears on my pieces. 

[glassobsessed]

A 'flea bite' is just a chip, it's an expression that some sellers use to make the damage sound smaller or less serious.

Here are a few photos of a stress crack, an air bubble, a chip and what I think of as 'straw marks'.

[Anik R]

John, I don't agree that a 'flea bite' and a 'chip' can be considered the same type of damage...  My understanding of a flea bite is damage which is so minuscule, it cannot be measured though it is visible (Photo 1).  A chip is a substantial, measurable piece of glass which is missing (Photo 2).  

I support px's idea of having an easily accessible area/thread which names, explains and shows different phenomena appearing in glass.  As I am new to the glass collecting world, my knowledge and understanding of glass-related vocabulary is limited.   And I really don't think turning to ebay to improve our glass-related vocabulary is the answer -- half (if not more) of what you read on these on-line auction sites is a bunch of bull.  

Proof?  My amethyst bullet vase was listed as a "Rare inter-war Murano vase in perfect condition".