Would love to see a good picture of the base.
Is that a clear band at the top of the rim?
Can you see mold marks?
Linda C

It's solid blue, no clear bands. There are very faint seam marks down the side and four raised dots on the bottom edges. I'll take a shot of the bottom of the vase tomorrow in the daylight and post it.

Here's a pic of the bottom of the vase.

Here is a link that might be useful:

Sorry....that has me stumped. I have never seen glass marked like that.

c markings, all around bottom of my cobalt blue vase

You don't say if it's vintage or not, and I really can't say either. One of my DD's received flowers in what looked to be a cobalt vase several years ago, but it was probably just plain, blue glass. Could it be fairly new and a product used by florists, such as FTD? ;o)

That blue glass is "cobalt" no matter if it's FTD stuff or centuries old....cobalt blue is cobalt blue.
And no that vase the OP posted is not FTD stuff...likely depression era.
Linda c

Are you the one who has it on Ebay for fifty dollars?

Linda, I think there are various techniques(chemicals)used in getting the glass to the deep blue color.

Cobalt glass is a deep blue colored glass prepared by adding cobalt compounds to the molten glass. It is appreciated for its attractive color. It is also used as an optical filter in flame tests to filter out the yellow flame caused by the contamination of sodium, and expand the ability to see violet and blue hues. Under fluorescent light, cobalt glass has twice the effect.

Some people collect objects made from cobalt glass, amassing large collections. One popular example of cobalt glass is Bristol blue glass, as in the distinctive blue bottles of Harvey's Bristol Cream sherry. Cobalt glass changes the color of hydrochloric acid in a mixture of multi-colored cations.
[edit] For pigment use

Powdered cobalt glass, called smalt (or also simply cobalt glass), has been historically important as a pigment in painting, pottery, and other media. Cobalt glass and smalt are made from silica and are not the same as cobalt blue, which is colored by cobalt ion is a similar way, but using a melting process with alumina.
[edit] See also

* Smalt
* Cobalt blue
* Cobalt

Don't believe 100% of what you read on Wikipedia. And if you copy and paste you should give credit.

No element but cobalt gives glass that color.

Bristol glass can be many colors. It is a designation for glass, usually opaque or semi opaque and decorated with enamel. Bristol Blue Glass was and I think still is, made in Bristol for sherry and various other products.

Sorry Linda, I don't want to take credit for what I posted, but didn't think it was relevant if I copy/pasted.

I'm such a lay person when it comes to glass and other vintage/antique things, so usually believe everything I read. You seem very knowledgeable re:antiques/vintage, so i'll take your word. ;o)

"Don't believe 100% of what you read on Wikipedia."

Never a truer statement. Wikipedia is really not reliable.
Diane

I have two vases exactly like yours which belonged to my great grandmother. I remember seeing them on her headboard when I was small, maybe in the 1970s, so they are at least pretty old. I sure would like to know more about them if anyone finds anything!