Cobalt Blue Glass

Cobalt Blue Glass
from the
Glass Encyclopedia

Cobalt blue glass

Cobalt blue vase
by Garry Nash
made c. 1997.

If you are looking for
Cobalt Blue Glass there
is always some for sale
on eBay. See what there
is just now - click
Cobalt blue glass

Cobalt Blue Glass: A short explanation:

Cobalt blue glass is normally a deep rich blue like the vase on the left. It is made by incorporating cobalt oxide in the molten glass mixture.

Most blue glass is given its color either from cobalt oxide or from copper oxide added to the molten glass. Copper is a more delicate colorant than cobalt. It only requires a small amount of cobalt oxide to produce a deep rich blue.

Cobalt is a metal, found in copper and nickel ores in many countries, but mined chiefly in Africa, USSR, Australia, Canada and smaller amounts in other countries. It was discovered by a Swedish chemist, Georg Brandt, in 1742; although the coloring properties of the ore has been known since very ancient times. There was even one piece of cobalt blue glass in Tut-Ankh-Amen's tomb in Egypt.

Before the 1920s the world's production of cobalt was primarily used as a glass and ceramic colorant. Since then it has been used increasingly in metal alloys, and over 80% of today's production of cobalt is used as a metal, - it is, for example, a component of the best magnets. Surprisingly it also makes up 4.3% of vitamin B12.

Small amounts of cobalt (around 1 ounce per ton of glass) are used to neutralise the yellow tint of iron in glass such as window glass. To produce a blue colour in glass, you only need to add five ounces to a ton of glass. Deeper blues are obtained by adding up to ten pounds of cobalt oxide to a ton of glass. This deep blue glass can then be ground up into a powder called "SMALT" which is used as a coloring agent for enamel, for glazes on pottery, and for making more blue glass.

Whilst cobalt oxide produces a deep royal blue, there are other compounds of cobalt which produce different colors. Cobalt aluminate makes turquoise glass; cobalt silicate produces violet-blue glass. Cobalt oxide added to borosilicate glass produces a purple or red glass.

There are many famous types of blue-colored glass which are in fact cobalt blue glass. Bristol Blue is one of the most famous. Fenton's blue carnival glass is a cobalt blue. So is Fenton's Royal Blue and Periwinkle Blue (both from the 1930s), their Blue Silvertone in the Sheffield pattern and Velva Blue from 1981. The Cambridge Glass Company used cobalt for their Royal Blue and their Moonlight Blue. Heisey called their cobalt blue "Steigel Blue"; and Fostoria produced two cobalt blues which they called "Regal Blue" and "Azure Blue".

Cobalt blue is one of the most popular colors in glass. Frank M. Fenton wrote that he had observed that blue glass sold quicker and for a better price than any other color.

The Hazel Atlas company produced their Shirley Temple mugs and tableware in cobalt blue with a white decal likeness of the child actress, beginning in the early 1930s and continuing to the 1950s. These, like several other cobalt blue patterns in depression glass, have been reproduced in recent years.

There is a story that the Hazel Atlas company had a large vat of cobalt blue glass left from making a planned quantity of Shirley Temple items, and decided to use it up by producing some of their other lines in cobalt blue. This is how the Moderntone pattern and Royal Lace pattern came to be produced in Deep Blue. The popularity of these lines encouraged many other Depression era glass makers to produce cobalt blue glass.

It is always interesting to see what cobalt blue glass items are for sale, click Cobalt blue glass to take a look.

Glass Encyclopedia

Click here for the full
list of latest topics

or click on any of
the following links:

Advertising glass
Akro Agate glass
Amberina glass
American glass
Ancient glass
Apothecary glass
Apsley Pellatt glass
Art Deco glass
Art nouveau glass
Arts and Crafts glass
August Walther Glass
Baccarat glass
Bagley glass
Barolac glass
Beads (glass)
Bimini glass
Blenko glass
Books on glass
Bottles (glass)
Boyd's Crystal Glass
Brierley Crystal glass
E O Brody glass
Bubble glass
Burtles Tate glass
Caithness glass
Cameo glass
Cameo incrustations
Carnival glass
Cast glass
Chance glass
Charder glass
Cire Perdue glass
Cloud glass
Cobalt blue glass
Consolidated glass
Contemporary glass
Coralene glass
Coudersport glass
Crackle glass
Cranberry glass
Custard cups (glass)
Custard glass
Cut crystal glass
Dartington glass
Daum glass
Davidson's glass
Depression glass
Dew drop glass
Dorothy Thorpe glass
Drinking glasses
DVDs on Glass
EAPG glassware
End-of-day glass
Etling glass
European glass
Fairy Lights
Federal glass
Fenton glass
Fire-King glass
Flygsfors glass
Fostoria glass
Frank Thrower glass
French glass
Fry Glass
Galle Glass
Glass hand vases
Glass Dumps
Gold ruby glass
Goofus Glass
Gray-stan glass
Greeners glass
Hand vases
Hazel Atlas glass
Heisey glass
Historismus glass
Hobnail glass
Hunebelle glass
Imperial glass
Intaglio glass
Irradiated glass
Isle of Wight glass
Italian glass
Jack-in-Pulpit glass
Jade glass
James Derbyshire
Jeannette Glass
Joblings glass
Joe Rice glass
John Derbyshire
J Walsh Walsh glass
Kemple glass
King's Lynn glass
Komaromy glass
Lalique glass
Leerdam glass
Le Verre Francais
L G Wright glass
Libbey glass
Libensky glass
Lobmeyr glass
Loetz or Lotz glass
Lost wax technique
Malachite glass
Manchester glass
Marbles (glass)
Marqueterie de Verre
Mary Gregory glass
Mdina glass
Mercury glass
Milk glass
Molineux Webb glass
Monart glass
Murano glass
Nailsea glass
Nazeing glass
New Zealand glass
NZ paperweights
Northwood glass
Opalescent glass
Orient & Flume glass
Orplid glass
Orrefors glass
Pallme-Konig glass
Paperweights of NZ
Pate de Verre
Peachblow glass
Pearline glass
Percival Yates & Vickers
Perthshire Paperw'ts
Phoenix glass
Pictures on glass
Pilgrim glass
Pirelli glass
Powell glass
Pyrex glass
Riverside glass
Reverse paint on glass
Roman glass
Rose bowls
Royal Brierley glass
Ruby glass
Sabino glass
Scandinavian glass
Schneider glass
Shoes in glass
Silhouettes on glass
Silvered glass
Silver overlay glass
Slag glass
Sowerby glass
Spatter glass
Stained glass
St Clair glass
Steuben Glass
Stevens & Williams
Strathearn glass
Stretch glass
STS Abel Zagreb glass
Sulphides in glass
Sun changed glass
Thomas Webb glass
Tiara glass
Tiffany glass
Tiffin glass
Toothpick Holders
Tortoiseshell glass
Tudor Crystal glass
Uranium glass
Val St Lambert glass
Vasart glass
Vaseline glass
Venetian glass
Venini glass
Verlys glass
Videos on Glass
Vistosi Glass
Vitro Porcelain Glass
Walther Glass
Waterford Crystal
Webb Corbett glass
Webb, Thomas glass
Wedgwood glass
Westmoreland glass
Whitefriars glass
WMF glass
Ysart glass

Glass Message Board

Glass Museum on Line

Books on Glass

Glass Target Searches

Our Glass Blog

Useful glass links

References and Sources:

We have selected some new or recent books as well as some favourite classic books on Cobalt Blue Glass. Click on the book cover or title to see more information.

Bristol Blue 2013 Encyclopedia of Cobalt Glass 2009 Cobalt Blue Glass 2007 Cobalt Blue Glass 1999

Browse specialist books on Glass
- what's new?
- what did you miss?
The place to browse through interesting glass books -

INFORMATION about Bagley Glass!
Bagley Glass made a very pale version of cobalt blue glass from the 1930s to the 1970s. The first three editions sold out quickly.

The 4th Edition is now available and has received a rave response - more information, more and better pictures, new items identified as Bagley, a new helpful index, and more compehensive coverage. A truly comprehensive guide to help you identify Bagley Glass.
Click on the picture for more details.

Copyright (c) 1998 - 2021 Angela M. Bowey.
All rights reserved. Copying material from this page for
reproduction in any format is forbidden.

Written and designed by: Angela M. Bowey.
URL to this page: