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
2%
1%
93%
2%
75
flagFinland
3%
0%
92%
3%
52
flagthe United Arab Emirates
4%
4%
80%
9%
42
flagthe United Kingdom
10%
3%
79%
5%
664
flagGermany
11%
3%
78%
6%
270
flagthe Netherlands
10%
2%
78%
7%
103
flagSpain
10%
2%
78%
8%
46
flagCanada
10%
8%
75%
5%
56
flagPoland
14%
4%
74%
5%
19286
flagFrance
16%
5%
74%
3%
54
flagthe United States
9%
4%
72%
12%
862
flagNorway
7%
2%
70%
17%
41
flagUnknown
19%
4%
66%
8%
121
flagRepublic of Ireland
14%
5%
65%
14%
70
flagAustralia
17%
3%
65%
13%
58
flagDenmark
20%
0%
64%
16%
25
flagthe Philippines
16%
2%
59%
18%
37
flagMalaysia
18%
7%
59%
14%
27
flagIndia
18%
8%
57%
12%
352
flagPakistan
38%
11%
23%
20%
34

Gender

men71%
women78%
ink
13%
12%
lead
6%
4%
cobalt
71%
78%
magnesium
7%
4%

Language versions

question
answers
results
flag
What was added to this glass to make it blue?
1988
66%

Details

Author: globalquiz.org
Illustration: Steven Depolo
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