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
flagItaly
1%
1%
93%
3%
58
flagFinland
4%
0%
91%
4%
48
flagSpain
9%
2%
78%
9%
42
flagthe United Kingdom
11%
4%
77%
6%
544
flagGermany
12%
4%
77%
5%
247
flagCanada
9%
7%
76%
5%
52
flagthe United Arab Emirates
8%
0%
76%
16%
25
flagPoland
15%
4%
73%
5%
17166
flagFrance
18%
6%
72%
4%
50
flagthe United States
9%
4%
71%
13%
778
flagthe Netherlands
14%
3%
71%
10%
77
flagNorway
7%
2%
70%
17%
40
flagUnknown
20%
5%
69%
5%
59
flagAustralia
19%
1%
66%
11%
51
flagRepublic of Ireland
17%
5%
61%
15%
57
flagthe Philippines
16%
2%
61%
16%
36
flagMalaysia
20%
4%
60%
16%
25
flagDenmark
21%
0%
60%
17%
23
flagIndia
17%
8%
58%
12%
328
flagPakistan
34%
12%
25%
21%
32

Gender

men70%
women78%
ink
14%
12%
lead
7%
4%
cobalt
70%
78%
magnesium
8%
4%

Language versions

question
answers
results
flag
What was added to this glass to make it blue?
1828
66%

Details

Author: globalquiz.org
Illustration: Steven Depolo
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