What was added to this glass to make it blue?

ink
lead
cobalt
magnesium
Powdered cobalt glass, called smalt, has been his­tor­i­cal­ly im­por­tant as a pigment in painting and pottery. It is colored to a deep powder blue hue using cobalt ions derived from cobalt oxide. Cobalt alu­mi­nate can be used in a similar way, and is now more common, often known as "cobalt blue".

Answers distribution

ink
lead
cobalt
magnesium
answers
flagFinland
3%
0%
93%
3%
58
flagItaly
2%
1%
92%
4%
89
flagSwitzerland
7%
1%
90%
0%
53
flagthe United Arab Emirates
3%
3%
87%
6%
63
flagthe Netherlands
7%
2%
83%
5%
171
flagthe United Kingdom
10%
3%
79%
5%
836
flagGermany
11%
3%
78%
6%
363
flagSpain
9%
1%
78%
9%
51
flagCanada
10%
9%
75%
4%
64
flagFrance
15%
5%
75%
5%
60
flagPoland
16%
4%
73%
5%
27124
flagthe United States
9%
3%
72%
13%
948
flagNorway
12%
3%
70%
12%
57
flagSweden
24%
5%
68%
1%
54
flagAustralia
17%
3%
65%
14%
64
flagRepublic of Ireland
17%
5%
63%
13%
91
flagUnknown
28%
4%
59%
6%
1258
flagthe Philippines
20%
2%
58%
16%
48
flagIndia
19%
8%
57%
12%
405
flagPakistan
35%
8%
35%
15%
45

Gender

men68%
women78%
ink
19%
13%
lead
5%
4%
cobalt
68%
78%
magnesium
6%
4%

Language versions

question
answers
results
flag
What was added to this glass to make it blue?
2286
66%

Details

Author: globalquiz.org
Illustration: Steven Depolo
tools
Should this question be improved? Improve it.
Globalquiz questions are translated by users for other users. Translate this question.