Hand blown cobalt blue glass semi-transparent cylindrical jug with spout on lip for pouring; concave bottom.
Number Of Parts
1
Provenance
Items belonged to donor, a physician from Ottawa.
Dates
1870
1890
circa 1870 - 1890
Date Remarks
Online research
Material
glass: blue
Permanent Location
Storage Room 0010
0010-A
Length
5.3
Diameter
4.8
Unit Of Measure
centimeters
Condition Remarks
Minor chip on edge of lip
Copy Type
original
Reference Types
Internet
Reference Comments
Cobalt Blue Glass. Glass Encyclopedia
Research Facts
Cobalt blue glass was made using oxide of cobalt or from copper oxide added to the molten glass.
Small amounts of cobalt (around one ounce per ton of glass) are used to neutralise the yellow tint of iron in glass such as windows. To produce a blue colour in glass, you need to only 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.
There was renewed interest in the dark blue glass in the late 1930s and dinnerware was made.