Satin Glass or Not? Any information

Hi -

I recently purchased these at an antique store. I have been interested in learning about Satin Glass, but keep coming up short on the internet, in library books, etc.

So, can any of you tell me something about these two items? Possibly tumblers? Or just pretty glass.

Thank you

 

The style would be called "mother of pearl" but I do not know whose.

 

The pattern is Diamond Optic Mother of Pearl satin glass.

What bothers me is the uneven top. I would think the tops would be more even across the top -

@Cherryhill

 

I cannot see what i need to see, but the originals of these, made in the late 19th century were ground and polished on the top, sometimes leaving the top cavities open. (Cavities?) the first gather of these on the blow pipe is blown into a mold which imparts ridges on the outside of the piece. It is then coated over with a very thin layer of glass, closing/sealing the diamonds. If the top row is ground leaving openings they can accumulate dirt, which shows up as black in the opening.

Modern pieces are fire polished, which seals the openings, but isn't flat as are the originals. Modern being Post WWII.

Before these are sold, they are subjected to a very light acid bath, leaving the exterior as 'satin.' Its the reflection off the inside of the bubble reacting with the satin which gives the MOP (mother of pearl) effect.

More than you wanted to know.

 

No, exactly what we needed to know.
Thank you. As always your explanations help a lot.

 

Thank you! I am interested in anything I can learn about these. Any suggestion for how I can tell if these are original or not? Happy to post more/better photos.

 

Look at the top surface. If it is shiny and very flat, it was ground and polished, therefore old. If it is wavy it's probably new.

Satin glass: Hydrofloric acid will etch the surface of glass, satin glass is exposed to the fumes (or in some cases dunked in acid) which gives it the smooth frosted surface.

 

Thank you.