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
0%
1%
94%
3%
53
flagFinland
6%
0%
86%
6%
30
flagCanada
10%
4%
81%
4%
48
flagBelgium
5%
5%
78%
10%
19
flagSpain
10%
2%
76%
10%
38
flagthe United Kingdom
12%
4%
75%
6%
455
flagGermany
15%
4%
74%
6%
199
flagPoland
16%
5%
72%
5%
15284
flagthe United Arab Emirates
11%
0%
72%
16%
18
flagthe United States
9%
4%
71%
13%
726
flagFrance
24%
2%
70%
2%
37
flagthe Netherlands
16%
5%
69%
8%
56
flagNorway
8%
2%
68%
17%
35
flagAustralia
20%
2%
65%
12%
49
flagRepublic of Ireland
15%
5%
62%
16%
53
flagDenmark
16%
0%
61%
22%
18
flagMalaysia
20%
4%
60%
16%
25
flagthe Philippines
18%
3%
59%
15%
32
flagIndia
18%
8%
57%
12%
297
flagPakistan
34%
7%
26%
23%
26

Gender

men69%
women77%
ink
15%
12%
lead
7%
5%
cobalt
69%
77%
magnesium
8%
4%

Language versions

question
answers
results
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What was added to this glass to make it blue?
1684
66%

Details

Author: globalquiz.org
Illustration: Steven Depolo
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