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%
92%
2%
70
flagFinland
4%
0%
91%
4%
49
flagthe United Kingdom
10%
3%
78%
6%
600
flagGermany
11%
3%
78%
5%
261
flagSpain
10%
2%
78%
8%
46
flagthe United Arab Emirates
5%
5%
77%
11%
36
flagthe Netherlands
12%
3%
75%
9%
88
flagCanada
10%
8%
75%
5%
56
flagPoland
15%
4%
74%
5%
18584
flagthe United States
9%
4%
72%
12%
847
flagFrance
18%
6%
72%
4%
50
flagNorway
7%
2%
70%
17%
40
flagAustralia
17%
1%
67%
12%
56
flagUnknown
20%
4%
65%
8%
105
flagRepublic of Ireland
15%
4%
64%
15%
65
flagDenmark
20%
0%
64%
16%
25
flagthe Philippines
16%
2%
61%
16%
36
flagMalaysia
18%
7%
59%
14%
27
flagIndia
18%
8%
58%
12%
344
flagPakistan
36%
12%
24%
21%
33

Gender

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

Language versions

question
answers
results
flag
What was added to this glass to make it blue?
1943
66%

Details

Author: globalquiz.org
Illustration: Steven Depolo
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