Help:PTCC
The periodic table as shown in the English wikipedia (enwiki) uses categories to mark the metallicity of the elements. Each category has its legend color. Both the label "category" and its associated color are editorial choices (chosen by enwiki editors).
The categorisation is based on science, WP:RS. The colors used are chosen wiki-local.
Periodic table
{{Periodic table}}
On commons
:See
::commons:Category:Periodic table using enwiki color scheme
::commons:Category:Periodic tables using the enwiki classifications
:::commons:Category:Periodic tables on enwiki (not conformed)
:::commons:Category:Periodic tables using enwiki classifications (outdated)
:::commons:Category:Periodic tables using enwiki classifications (translated)
Talk central
Discussions are at WT:ELEMENTS. You are invited.